Rhodium-Catalyzed Decomposition of Carbohydrate Diazo Esters By

Home , Carbohydrate chemistry, Diazo, Tosyl group

Rhodium-Catalyzed Decomposition of Carbohydrate Diazo Esters

Matthew LaLama

Submitted in Partial Fulfillment of the Requirements

for the Degree of

Master of Science

in the

Chemistry

Program

YOUNGSTOWN STATE UNIVERSITY

August 2018

Rhodium-Catalyzed Decomposition of Carbohydrate Diazo Esters

Matthew LaLama

I hereby release this thesis to the public. I understand that this thesis will be made available from the OhioLINK ETD Center and the Maag Library Circulation Desk for public access. I also authorize the University or other individuals to make copies of this thesis as needed for scholarly research.

Signature:

Matthew J. LaLama, Student Date

Approvals:

Dr. Peter Norris, Thesis Advisor Date

Dr. Douglas Genna, Committee Member Date

Dr. John Jackson, Committee Member Date

Dr. Salvatore A. Sanders, Dean of Graduate Studies Date

iii

ABSTRACT

This thesis herein reports the synthesis of two diazo ester sugars and their decomposition in the presence of catalytic rhodium acetate dimer. Reactions were designed for the isolation of products formed through intramolecular C-H insertion reactions. However, no C-H insertion occurred, and instead this research led to the formation of a head-to-head- imine linked dimer not presently reported by previous lab members.

Acknowledgements

Firstly, I would like to thank Dr. Peter Norris, my advisor, for providing me with the opportunity to be a member of his research group. From providing me with my sophomore organic education, to his advice and tutelage while working as an undergraduate and graduate student in his lab, he has helped every step of the way. Thank you for all of your help, and thank you for playing a part in convincing me to become a chemistry major.

I would like to thank my committee members, Dr. John Jackson and Dr. Douglas

Genna. Throughout my time at YSU, Drs. Jackson and Genna have been instrumental towards my chemical upbringing. If I ever had questions, their doors were always open and they were willing to lend a hand. I learned so much from both of their classes and it was the cultivation of this knowledge and of laboratory technique that has brought me this far.

A special thank you must go out to Dr. Matthias Zeller. Dr. Zeller acted as my first undergraduate research advisor, under who’s tutelage and training gave me insight into a realm of chemistry and chemical techniques I otherwise would know nothing of.

Dr. Zeller is also the person who had the most influence in leading me to become a chemist. His knowledge and passion for the field and his job inspired me to carry on my study of it, and for that I cannot thank him enough.

I would like to thank past and present members of the Norris lab for their support and friendship throughout my years here. As well as my fellow graduate students from other lab groups. From the day I entered as an undergraduate until now, you have all been v nothing short of a second family to me. I’m thankful for your support and wish you all the best in your own future endeavors.

I would like to extend my gratitude to Tim Styranec and Troy James Jr. in chemical management. Their expertise in chemical safety, promptness in providing chemicals and lab equipment, and general support over the years are greatly appreciated.

Finally, I would like to extend a thanks to my family. My mother and father, who supported me every step of the way. Their constant love and encouragement throughout the years has been nothing short of a blessing.

Thank you, to all my friends and family!

Table of Contents

Title Page…………………………………………………………………………………..i

Signature Page………………………………………………………………….…………ii

Abstract…………………………………………………………………………………...iii

Acknowledgments………………………………………………………………………..iv

Table of Contents………………………………………………………………………....vi

List of Figures……………………………………………………………………………vii

Introduction………………………………………………………………………………..1

Natural Products………………………………………………………………………...... 1

Carbohydrates……………………………………………………………………………..4

Azides..…………………………………………………………………………………....6

Diazo Compounds…………………………………………………………………………8

Transition Metal-Catalyzed Ractions………………………………………………...…...9

Statement of Problem…………………………………………………………………….13

Results and Discussion………………………………………………………………...... 14

Conclusion...... 27

Experimental……………………………………………………………………………..28

References………………………………………………………………………………..43

vii

List of Figures

Figure 1: Structures of natural products xylobovide, sporothriolide, and canadensolide which feature fused γ-butyrolactone structures…………………………………………...2

Figure 2: Structure of plakortones A, B, C, and D……………………………………….3

Figure 3: Stucture of secosyrins 1 and 2………………………………………………….3

Figure 4: Fischer projections of Fructose, D-Glucose and L-

Glucose……………………………………………………………………………………4

Figure 5: A mono- and di-protected carbohydrate platform……………………………...6

Figure 6: Resonance forms of a generic organic azide…………………………………...7

Figure 7: Structure of a generic diazo group……………………………………………..8

Figure 8: Structures of dirhodium(II) catalysts with carboxylate and carboxamidate ligands……………………………………………………………………………………11

Figure 9: Crystal structure of azine 4……………………………………………………19

Figure 10: Structures of the ether-linked dimer and the 14 membered macrocycle isolated by Malich………………………………………………………………………..27

Figure 11: 1H NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D- glucofuranose (2)………………………………………………………………………...48

Figure 12: 13C NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D- glucofuranose (2)………………………………...…………………………………..…..49

Figure 13: COSY NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D- glucofuranose (2)………………………………………………………………………...50

Figure 14: IR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D-glucofuranose

(2)………………………………………………………………………………………...51 viii

Figure 15: 1H NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacyldiazo)-α-D- glucofuranose (3)………………………………………………………………………...52

Figure 16: 13C NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacyldiazo)-α-D- glucofuranose (3)………………………………………………………………………...53

Figure 17: IR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacyldiazo)-α-D- glucofuranose (3)...... 54

Figure 18: 1H NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacylhydrazine-

1,2-diylidene)-α-D-glucofuranose (4)……………………………………………………55

Figure 19: 13C NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacylhydrazine-

1,2-diylidene)-α-D-glucofuranose (4)……………………………………………………56

Figure 20: COSY NMR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-

(phenacylhydrazine-1,2-diylidene)-α-D-glucofuranose (4)……………………………...57

Figure 21: IR spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacylhydrazine-1,2- diylidene)-α-D-glucofuranose (4)………………………………………………………..58

Figure 22: Mass spectrum of 1,2:5,6-di-O-isopropylidene-3-O-(phenacylhydrazine-1,2- diylidene)-α-D-glucofuranose (4)………………………………………………………..59

Figure 23: 1H NMR spectrum of 1,2-O-isopropylidene-α-D-xylofuranose (6)…………60

Figure 24: 13C NMR spectrum of 1,2-O-isopropylidene-α-D-xylofuranose (6)………...61

Figure 25: IR spectrum of 1,2-O-isopropylidene-α-D-xylofuranose (6)………………..62

Figure 26: 1 H NMR spectrum of 1,2;3,5-di-O-isopropylidene-α-D-xylofuranose (7)....63

Figure 27: 1H NMR spectrum of 5-O-(4-methylbenzenesulfonyl)-1,2-O-isopropylidene-

α-D-xylofuranose (8)...... 64 ix

Figure 28: 13C NMR spectrum of 5-O-(4-methylbenzenesulfonyl)-1,2-O-isopropylidene-

α-D-xylofuranose (8)…………………………………………………………………….65

Figure 29: COSY NMR spectrum of 5-O-(4-methylbenzenesulfonyl)-1,2-O- isopropylidene-α-D-xylofuranose (8)……………………………………………………66

Figure 30: COSY NMR spectrum of 5-O-(4-methylbenzenesulfonyl)-1,2-O- isopropylidene-α-D-xylofuranose (8)……………………………………………………67

Figure 31: 1H NMR spectrum of 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose

(9)………………………………………………………………………………………...68

Figure 32: 13C NMR spectrum of 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose

(9)……………………………………………………………………………………...... 69

Figure 33: COSY NMR spectrum of 5-azidodeoxy-1,2-O-isopropylidene-α-D- xylofuranose (9)………………………………………………………………………….70

Figure 34: IR spectrum of 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose (9)...71

Figure 35: 1H NMR spectrum of 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (10)…………………………………………………..72

Figure 36: 13C NMR spectrum of 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (10)…………………………………………………..73

Figure 37: COSY NMR spectrum of 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (10)…………………………………………………..74

Figure 38: IR spectrum of 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O-isopropylidene-α-

D-xylofuranose (10)……………………………………………………………………...75

Figure 39: 1H NMR spectrum of 3-O-(2-Diazo-2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (11)…………………………………………………..76 x

Figure 40: 13C NMR spectrum of 3-O-(2-Diazo-2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (11)…………………………………………………..77

Figure 41: 13C NMR spectrum of 3-O-(2-Diazo-2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (11)…………………………………………………..78

Figure 42: 1H NMR spectrum of decomposition product of MAX diazo ester 11...... 79

Figure 43: 13C NMR spectrum of decomposition product of MAX diazo ester 11...... 80

Figure 44: COSY spectrum of decomposition product of MAX diazo ester 11…...……81

Figure 45: HSQC spectrum of decomposition product of MAX diazo ester 11………...82

Figure 46: IR spectrum of decomposition product of MAX diazo ester 11………….....83

Figure 47: X-ray crystal structure of azine 4……………………………………………84

Introduction

Natural Products

Natural product synthesis is the art of constructing naturally-derived, complex molecules normally found in biological systems in a laboratory setting. These natural products often exhibit important pharmacological and biomedical properties, which allows them to be used in a multitude of ways, including in antitumor, antibacterial, antifungal, and herbicidal applications.1 The demand to synthesize natural products in an efficient manner, as well as obtaining a large quantity of product, often serves as a driving force for the discovery of new chemical reactions as well as testing the limits of existing reactions.

Chemical compounds derived from natural sources exhibit complex structures featuring macrocyclic systems or a wide array of functionality in the various groups on the molecule. One particular example of these types of molecules is erythromycin, whose synthesis was first reported in 1981.2 Erythromycin is a useful antibiotic for the treatment of various infections such as respiratory tract infection, skin infections, chlamydia, and syphilis. Despite the interesting applications of large macromolecular cycles, there are also plenty of smaller-scale natural products that can be used for medicinal purposes.

Structural interest in natural product synthesis is oftentimes focused on secondary metabolites but in the synthesis of biologically and pharmacologically active molecules, primary metabolites play a fundamental role in synthesis. Primary metabolites are small molecules, including fats, lipids, amino acids, and carbohydrates that play key roles in growth, development, and reproduction in organisms. 2

The focus of the current research is limited to one such naturally derived structure, which is comprised of two fused γ-butyrolactone rings that serve as the backbone for the structure (Figure 1). These specific lactones are cyclic systems with 4 carbons containing an ester motif. These types of natural compounds are typically derived from a fungal source such as Xylaria obovate, Sporothrix schenckii, as well as

Penicillium canadense. Respectively, these fungi provide the natural products xylobovide, sporothriolide and canadensolide, which are sought for their antifungal, antibacterial and phytotoxic properties (Figure 1). These compounds have been synthesized by Thongyoo et al. in the laboratory via the use of dimethyl itaconate-anthracene adducts.3, 4

Figure 1: Structures of natural products xylobovide, sporothriolide, and canadensolide

which feature fused γ-butyrolactone structures.

Another group of natural products featuring a derivative of the bis-γ- butyrolactone structure is the plakortone family. Plakortones are considered secondary metabolites and are found in Plakortis halichondrioides, a species of Caribbean sponge

(Figure 2). Plakortones are biologically active furanolactones and their most notable use is in the activation of the SR-Ca2+-pumping ATPase which can fix irregularities that may occur during cardiac muscle relaxation.5 3

Figure 2: Structure of plakortones A, B, C, and D.

Secosyrins are another class of compounds containing a bisfuran ring system.

However, the structure adopts a spiro bicyclic arrangement in which the rings are linked at a mutual carbon center as opposed to two different carbons (Figure 3). These secosyrin compounds are derived from the Pseudomonas syringae Pv. tomato and are a co-product with syringolide which features three linked furan-like rings.6,7 These syringolide-derived compounds elicit responses on soybean plants that carry the Rpg4 resistance gene. While secosyrins’ effects are currently unknown, they have been isolated and synthesized due to their potential role in the response process as well as for the tertiary chiral center present in their structure.7

Figure 3: Stucture of secosyrins 1 and 2.

Carbohydrates

Carbohydrates are some of the most abundant organic molecules on the planet and they can be found in many places in nature, ranging from plants, animals, and the human body. These molecules are also complex in structure, featuring varying centers of chirality, which has led chemists to turn to them as cheap, chiral starting materials.

Carbohydrates also feature a diverse range of functionalities, including structural support in cellulose as well as serving as the backbone for nucleic acids (DNA/RNA).8 They exist in three forms: a monosaccharide, a single sugar unit, an oligosaccharide, 2-10 saccharides that are linked in chains via nitrogen or oxygen linkers, and polysaccharides, long chains of saccharides connected via glycosidic linkages. Monosaccharides usually exist as a cyclic ring structure depicted in an envelope conformation and they can exist in one of two forms: the aldose form, such as glucose which features an aldehyde in its linear chain depiction (Fischer projection), or a ketose, such as fructose, which features a ketone in its Fischer projection. These compounds, possessing inherent chirality, often exist in a D or L configuration, in which the second to last hydroxyl group in the Fischer projection is facing either to the right or left respectively (Figure 4).

Figure 4: Fischer projections of Fructose, D-Glucose and L-Glucose.

Two naturally-occurring types of carbohydrate derivative are glycosides and branched-chain sugars. The branched-chain sugars occur when a non-terminal carbon has a carbon substituent group rather than the alcohol, and glycosides are formed when a covalent bond is formed between the hemiketal/hemiacetal of the saccharide derivative and some other molecule which may or may not be another carbohydrate. The glycoside compound is referred to as either C-, N-, O-, or S-glycoside in accordance with whether the group is –CR, -NR2, -OR, or –SR, respectively.

Branched-chain sugars can be synthesized through multiple methods, with some of the most common methods involving the use of Grignard reagents, epoxide openings, conjugate 1,4-addition, the use of radicals, and the Wittig reaction.9,10 The natural complexity of monosaccharides in terms of both chirality and functionality brings forth the need to ensure that a reaction occurs at the desired location. In order to selectively alter a carbohydrate molecule, other reactive sites must be blocked through the use of protecting groups. Standard protecting groups for carbohydrates include acetate, which forms an ester protecting group in place of a hydroxyl, and isopropylidene groups, which protect two hydroxyls at once.11

D-Xylose is an excellent candidate as a branched-chain sugar precursor.

Possessing four hydroxyl groups in the xylofuranose form, some of the alcohols must be protected with the isopropylidene group in order to utilize its structural features. An acid- catalyzed reaction between D-xylose and acetone can yield two outcomes, in one instance, a monosubstituted product in which an isopropylidene group protects the two hydroxyls at carbons 1 and 2, and a disubstituted product in which the isopropylidene protects all of the hydroxyl groups on the structure12 (Figure 5). In addition to this, the 6 incorporation of an isopropylidene group to the C-1 and C-2 hydroxyl groups can assist in locking carbohydrates into their furanose forms.

Figure 5: A mono- and di-protected carbohydrate platform.

Azides

The azide functional group is a useful tool in the realm of natural products total synthesis. An azide is a linear functional group comprised of three nitrogen atoms

(Figure 6). Azides feature both a positive and negative formal charge in conjunction and can distribute electrons through the system. Azides play a role in many reactions, including the Huisgen cycloaddition (as in “click” chemistry), the Curtius rearrangement,

Schmidt rearrangement, and the Staudinger reduction.13 Azides are classed as pseudohalides as they act in a similar fashion to that of a halogen. While azides are useful, they also pose potential hazard and warrant caution when working with them.

Through the input of external energy, such as pressure, heat or impact, azides are explosive substances that decompose with the release of nitrogen. While stable versions of the anion exist, such as sodium azide (NaN3), the covalently-bound and heavy metal versions risk thermal decomposition.13 In order for these compounds to be utilized safely a rule exists in which (NC + NO)/(NN) ≥ 3 in which N is the number of atoms, and subscripts C, O, and N pertain to carbon, oxygen, and nitrogen respectively.13

Figure 6: Resonance forms of a generic organic azide.

Azides can be used as a nitrogen source in the synthesis of nitrogen-containing compounds. A commonly occurring inorganic azide source is NaN3. Alkyl azides can be synthesized by a nucleophilic substitution reaction (SN2), where the azide acts as a nucleophilic species and attacks a carbon center with a good leaving group, causing inversion of stereochemistry in the product of the reaction. One example of this such reaction can be seen in Equation 1, where the glucosyl bromide reacts with sodium azide to form a glucosyl azide with inversion at the anomeric carbon. Upon isolation and purification, the versatile azide group can be used in substitution, elimination, addition and other types of reactions.12

Equation 1.

Diazo Compounds

Figure 7: Structure of a generic diazo group.

Azides can be used as diazo transfer compounds, which introduce a new motif consisting of two nitrogen atoms bound to a carbon with the generic structure R2C=N2

(Figure 7). The central nitrogen atom possesses a formal positive charge, while a lone pair delocalizes between the bound carbon and the terminal nitrogen atom. While simple diazo groups are relatively stable, α-diazoketones and α-diazoesters exhibit superior stability due to their ability to delocalize the charge into the neighboring carbonyl.14, 15

The concept of diazo transfer was first discussed in 1910 by Dimroth and it has since been established that diazo transfer reactions are invariably performed by some sulfonyl/tosyl azide which acts as the donor group.16 Diazo transfer proceeds through a process in which a proton in the position alpha to a carbonyl is deprotonated by a strong base inducing formation of an enolate. The resulting carbanion can then attack the terminal nitrogen of the azide. Subsequent intramolecular deprotonation of another alpha proton will occur and the electrons will push into the azide ultimately releasing a molecule of p-toluene sulfonamide and forming the newly double-bonded diazo carbonyl species (Scheme 1). 9

Scheme 1.

Transition Metal-Catalyzed Reactions

Diazo carbonyl compounds can be decomposed in the presence of a transition metal catalyst in order to prepare cyclic systems. These reactions form a metal-stabilized carbene intermediate following the displacement of the nitrogen. This electrophilic carbene can then be transferred to an electron-rich substrate allowing for regeneration of the metal catalyst.17 The reacting substrate can be a variety of compounds such as an alkene, alkane, C-H, N-H, S-H, carbonyl species, etc. Carbenoid insertion chemistry can also proceed via an intermolecular or intramolecular pathway. However, in regards to the current research, the intramolecular reaction, illustrated in Scheme 2, is the more concerning process following diazo decomposition. 10

Scheme 2: Proposed mechanism for intramolecular Rh-catalyzed C-H activation.

Different transition metals such as copper, zinc, palladium, and rhodium are utilized in catalytic decomposition reactions. This research will focus solely on the use of rhodium(II)-catalyzed reactions; mainly the Rh-Rh diamagnetic dimers, which exist as the most common form.18 A large array of bridging ligands can be attached to the central

Rh-Rh complex in order to form numerous dirhodium species. These catalytic species are of interest due to their ability to better control the selectivity of the insertion pathway.17, 19

Normally, intramolecular C-H insertion reactions yield multiple products and tend to demand highly electrophilic catalysts in order to favor a more selective reaction.20, 21

There exists two major groups of dirhodium(II) catalyst complex which differ in bridging ligands, namely carboxylate or carboxamidate (Figure 8). Dirhodium(II) tetraacetate,

Rh2(OAc)4, acts as the parent catalyst for the others. This structure leaves a vacant site in the metal’s coordination sphere for carbene binding following the association of four bridging acetate ligands. The replacement of the bridging acetates with varying carboxylate or carboxamidate ligands allows for the formation of a wide range of unique 11 catalysts. The variance of these catalysts allows for systems which can be tuned to promote specific reactivity and selectivity in a reaction.22

Figure 8: Structures of dirhodium(II) catalysts with carboxylate and carboxamidate

ligands.

In the absence of a diazo group, it has been reported that the azide functionality will associate with the rhodium catalyst to promote intramolecular C-H amination.

Different catalysts were tested resulting in yields that range from as low as 9% to >95%.

This process is shown in Scheme 3 highlighting the optimal conditions for the reaction utilizing a perfluorobutyrate rhodium (II) species to catalyze the reaction.23

Scheme 3.

Since their discovery, dirhodium (II) carboxylates and carboxamidates have become the go-to catalysts to facilitate diazo decomposition while generating a new C-C bond in the process. However, this process can shut down in the form of two competing 12 pathways; one is the formation of a carbene dimer of the diazo carbon and the other is a water insertion process in which a molecule of water adds as a hydroxyl and is subsequently oxidized to the corresponding carbonyl (Scheme 4). These pathways can be minimized through careful technique and by varying experimental parameters. Studies have shown that during formation of the five-membered rings, that insertion into a tertiary C-H bond is more favorable than a secondary and primary C-H bond respectively.22 It should also be noted that a heteroatom neighbor, such as oxygen, can activate the C-H bonds for insertion reactions and that the presence of an electron- withdrawing group will inhibit the C-H insertion.24, 25

Scheme 4.

The focus of this research has divergent directions with overlapping methods.

Initially, the focus is set on the synthesis of a bis-γ-butyrolactone structure which mimic the base structure of multiple natural products. The second focus for this research involves the effects of an azide moiety present on a carbohydrate platform and any effects it may have on the outcome of a rhodium(II)-catalyzed carbenoid C-H insertion reaction.

Currently, two potential outcomes for C-H insertion exist in the modified xylofuranose platform; the position alpha to the azide at C-5 and the C-2 position in the ring. We seek to understand possible directing effects of the azide in the route of this reaction.

Statement of problem

The synthesis of naturally-derived chemical compounds is a major goal in organic chemistry. Carbohydrates will be used as a platform in the synthesis of these compounds.

Introduction of an ester moiety followed by subsequent diazo transfer will provide a platform to undergo rhodium-catalyzed decomposition. The results will be studied to determine the fate of the projected carbenoid intermediate as well as any effects neighboring functional groups may play in the reaction.

Results and Discussion

Carbohydrates are excellent sources of synthetic intermediates which possess multiple areas of chirality. The multiple hydroxyl groups present on each monomer tend to be reactive and as such must be functionally protected in order to control reactivity.

Isopropylidene protecting groups play a key role due to their ability to protect two hydroxyls at one time. The installation of these groups are fairly straightforward, requiring a relatively small amount of catalytic acid with an excess of acetone.

For the first portion of the research the commercially available 1,2:5,6-di-O- isopropylidene-α-D-glucofuranose (DAG) (1) was used to synthesize the 1,2:5,6-di-O- isopropylidene-3-O-phenacyl-α-D-glucofuranose (2), a known compound, as depicted in

Equation 2. This reaction proceeds via Steglich esterification,26 which involves the reaction of a hydroxyl group with a carboxylic acid in order to install an ester to the system. The reaction results in a urea byproduct which is subsequently filtered off to obtain pure product. In this case, pure 2 was recovered as colorless crystals in 69% yield.

Equation 2.

Evidence to support the structure of 2 was seen in the 1H NMR spectrum. This confirmed the presence of both isopropylidene groups with four 3H singlets ranging from 15

1.26-1.50 ppm. The signal from the two protons α to the carbonyl was present at 3.66 ppm due to its location α to the phenyl and carbonyl groups. The doublet of doublets present at 4.01 ppm (J = 4.9, 8.6 Hz) and 4.10 ppm (J = 6.0, 8.5 Hz) accounted for protons H-6 and H-6’. Using 2D correlation spectroscopy (COSY) the signals for protons

H-1 through H-5 were determined. The multiplet from 4.05-4.10 ppm was determined to be the signal from H-5. The signal at 4.18 ppm appearing as a doublet of doublets (J =

3.1, 7.9 Hz), was determined to be H-4. H-2 was found as a doublet at 4.42 ppm (J = 3.9

Hz), the signal for H-3 appeared as a doublet at 5.28 ppm (J = 2.9 Hz), and the signal for

H-1, appeared far downfield due the presence of two O-neighbors, was found at 5.81 ppm

(J = 3.6 Hz). The protons on the phenyl substituent appeared as a 5H multiplet ranging

13 from 7.26-7.32 ppm. C NMR also showed the presence of signals at 41.35 ppm, -CH2- alpha to the ester, 112.31-133.42 ppm, which accounted for the phenyl group, and 170.04 ppm, which belonged to the ester carbonyl.

Further characterization was performed utilizing infrared spectroscopy (IR). In the

IR spectrum for 1, a broad signal is present at 3458 cm-1 which is indicative of the presence of a hydroxyl group in the starting material. When the IR spectrum of 2 was taken, the signal previously present at 3458 cm-1 was no longer present; instead a new signal appearing at 1740 cm-1 had now appeared, corresponding to the carbonyl group of the newly formed ester function. The new signal between 640 and 770 cm-1 also indicated the presence of the monosubstituted benzene ring from aromatic C-H bending in the structure. This is a known compound and the data found matches that of the data that was previously reported.27

Equation 3.

In the synthesis of diazo ester (3) (Equation 3), a diazo group was placed on the carbon α to the carbonyl as depicted in Equation 4. Purified 2 and the azide source, 4- nitrobenzenesulfonyl azide (p-NBSA) were dissolved in anhydrous dichloromethane. The base, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was added dropwise to the reaction mixture via syringe. The reaction was monitored with TLC and, upon completion, the mixture was washed with dilute H2SO4 and the organic layers rinsed with deionized water. The crude diazo compound was purified via flash column chromatography, which resulted in pure diazo ester 3 as an orange syrup in 66% yield.

Once again, product purity was verified via 1H NMR. The isopropylidene methyl groups remained intact and appeared between 1.24 and 1.54 ppm. Two signals, both doublets of doublets, at 4.01 ppm (J = 4.9, 8.6 Hz) and 4.10 ppm (J = 4.9, 8.6 Hz) corresponded to the H-6 and 6’ protons. The signal previously present that corresponded to the carbonyl α-protons was now gone, suggesting successful diazo transfer had occurred. Again, COSY spectroscopy was utilized to determine which signals corresponded to H-1 through H-5. The multiplet appearing between 4.16-4.20 ppm corresponded to H-5. The signal at 4.27 ppm appearing as a doublet of doublets (J = 3.0,

8.0 Hz) was identified as H-4 with COSY. The next signal at 4.67 ppm appeared as a 17 doublet with (J = 3.7 Hz) was assigned to H-2, and the signal at 5.39 ppm also appearing as a doublet with (J = 3.1 Hz) was assigned to H-3. The last doublet signal furthest downfield at 5.91 ppm (J = 3.6 Hz) corresponded to H-1. Between the range of 7.18-7.48 ppm appeared the 5H multiplet belonging to the phenyl group. In the 13C NMR the carbon signal for the α to carbonyl position had shifted downfield from 41.35 ppm to

67.24 ppm do to the presence of the diazo group.

Unlike the 1H NMR spectrum for 2 the spectrum for 3 did not display the carbonyl α-proton signals previously found at 3.66 ppm. The loss of this signal suggests that the diazo group was successfully added to the structure in the position α to the carbonyl. Further characterization of this compound was performed with IR spectroscopy. The IR spectrum 3 retained most of the same signals when compared to 2’s spectrum aside from the presence of a newly present signal at 2087 cm-1 which is indicative of the diazo species. This is a known compound and the data found matches that of the data that was previously reported.27

Equation 4.

The attempted decomposition of 3 was performed with use of a rhodium(II) acetate catalyst to induce an intramolecular reaction which was modeled after the work of previous students Patton28 and Malich29 (Equation 4). In a glove box, diazo ester 3 was 18

dissolved in anhydrous dichloromethane, and in a separate flask, Rh2(OAc)4 was suspended in anhydrous dichloromethane. The two solutions were then slowly added together over a period of 24 hours with the use of a syringe pump. Upon complete addition of the two solutions, TLC was taken and revealed the formation of two new spots at Rf = 0.56 for the high spot and Rf = 0.37 for the lower spot. Following flash column chromatography on silica gel (3:1/hexanes: ethyl acetate) to remove the

Rh2(OAc)4, the two separate products were eluted from the mixture.

1H NMR was utilized to characterize the two products. The spectrum for the upper spot’s spectrum had an intractable mixture of products, while the lower spot provided a clearer, more easily interpreted spectrum. Apart from some slight shifting in the signals, the spectrum was nearly identical to that of the diazo ester 3. When comparing the 13C NMR however, there appeared to be two signals present at 160 and

163 ppm at roughly half of the intensity of the other signals, which could possibly indicate the presence of two carbonyl groups. The lower spot was successfully recrystallized as yellow crystals from hot ethanol in 19% yield and provided a structure for azine 4 (Figure 9). 19

Figure 9: Crystal structure of azine 4.

Recent work done by Joseph Fox and his group have led to the synthesis of these compounds, which form as a precursor to hydrazones.30 The formation of these hydrazones can be useful in the synthesis of chiral quaternary α-amino esters. The formation of azine 4 is the first reported synthesis of this structure in the Norris lab. The proposed mechanism for the synthesis of azine 4 is depicted in Scheme 5. One equivalent of the diazo ester species forms a complex with the rhodium catalyst. The resulting carbine-like species then attacks the terminal nitrogen of the diazo group of another diazo ester 3. The double bond between the two nitrogen atoms then pushes electron density into the N-C bond which regenerates the catalytic rhodium species and releases a molecule of azine 4. Despite repetition of this experiment, no formation of the C-H insertion product was recorded. Instead, azine 4 was reproduced in another decomposition attempt. 20

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GLDFHWRQH'[\ORVH VSHFLHV (TXDWLRQ 7KHVKRUWHUWLPHWKHVROXWLRQZDVDOORZHG 21 to mix initially resulted in the favorability for the formation of the monoacetone xylofuranose (MAX) 6. After removal of sodium sulfate salts via gravity filtration, the resulting solution was then washed with dilute H2SO4 and deionized water. The resulting layers were checked for product and it was discovered that the more polar, monoacetone

D-xylose 6 was present in the aqueous layer while the diacetone D-xylofuranose 7 was found in the organic layer. The solutions were separately concentrated under reduced pressure and purified via flash column chromatography (30:1/CH2Cl2: MeOH).

Equation 5.

The 1H NMR spectrum was used to characterize the structures of both 6 and 7.

Notably, when comparing the two spectra, the spectrum for 6 contained only two 3H singlet peaks found at 1.32 and 1.49 ppm whereas the spectrum for 7 contained four separate 3H singlet peaks belonging to the two isopropylidene groups. A signal at 2.98 ppm, appearing as an apparent triplet (J = 5.9 Hz), was determined to be the -OH proton adjacent to C5 on xylofuranose. With the use of COSY NMR, protons H-1 through H-5 were assigned. The multiplet appearing at 4.00-4.18 ppm corresponded to H-5 and H-5’.

A singlet peak appearing at 4.09 ppm, which corresponded to a 1H signal, was determined to be the -OH group present on C3 of the xylofuranose platform. The signal present at 4.17 ppm (J = 3.0 Hz), which appeared as an apparent doublet, belonged to H-

4, and the apparent singlet at 4.32 ppm was determined to be the H-3 signal. The doublet at 4.52 ppm (J = 3.5 Hz) belonged to H-2, and the final signal furthest downfield at 5.98 22 ppm (J = 3.5 Hz) belonged to H-1 due to its position between two O-neighbors. These structures are both known compounds and the data found matches that of the data that was previously reported.

The next step was to introduce the azide moiety to 6, however in order to do so the remaining primary hydroxyl group had to be converted into a good leaving group. As such, compound 6 was dissolved in a small amount of pyridine, after which tosyl chloride was added slowly via solid addition funnel to the reaction mixture. The mixture was placed in an ice/acetone bath to promote tosylation of the primary alcohol ensuring minimal tosylation occurred at the C3 hydroxyl. The reaction was monitored by TLC and once completion was determined, methylene chloride was added and the mixture was washed with water and concentrated under reduced pressure. This process was repeated multiple times to remove excess pyridine, and the product 5-O-(4- methylbenzenesulfonyl)-1,2-O-isopropylidene-α-D-xylofuranose (8) was obtained as a white solid (Equation 6).

Equation 6.

Characterization was performed with the use of 1H NMR. The main factors for characterization were the loss of the apparent triplet hydroxyl signal from the previous compound and the new presence of two 2H doublets at 7.36-7.80 ppm (J = 8.0 Hz) and a

3H singlet peak at 2.45 ppm which correspond to the toluene motif of the tosyl protecting 23 group, indicating successful attachment of the group. This structure is a known compound and the data found matches that of the data that was previously reported.29

With the tosyl motif successfully in place, the next step was to add the azide group. Tosylated MAX 8 was reacted in an excess of sodium azide in dimethylformamide at 70 °C. Following removal of the solvent with dI H2O, further purification was performed via flash column chromatography (3:1 / hexanes: ethyl acetate), which resulted in a fibrous white solid (21% yield) of azide 9 (Equation 7). Evidence for the formation of the azide is present in the 1H and 13C NMR spectra in which the peaks corresponding to the tosyl group are no longer present and the H-5, H-5’ signals, at 3.59 (J = 5.8, 12.9

Hz), 3.64 (J = 6.5, 12.9 Hz) respectively, are now more distinct than in the spectrum of tosylated material 8. IR also provides insight in the form of a signal around 2100 cm-1 which accounts for the presence of the azide moiety. This is a known compound and the data found matches that of the data that was previously reported.29

Equation 7.

With the azide group in place, there is only one reactive hydroxyl left on azide 9 in the C-3 position. Once again, the Steglich esterification26 was employed in order to esterify the C-3 hydroxyl (Equation 8). After completion was determined by TLC, the resultant urea byproduct was removed via gravity filtration. Further purification was necessary and performed again via flash column chromatography (3:1 / hexane: ethyl 24 acetate), which resulted in the formation of the azidodeoxy phenacyl ester 10 as a colorless syrup (66%).

Equation 8.

Attempts to solidify and recrystallize the syrup proved unsuccessful, though the

1H NMR proved sufficient enough to confirm successful synthesis of ester 10. The 2H singlet present at 3.65 ppm corresponds to the CH2 group alpha to the carbonyl of the newly formed ester. The peak previously corresponding to the -OH group has also diminished. A new multiplet, at 7.38-7.48 ppm, correlating to the five phenyl hydrogens has also appeared in the spectrum. The IR spectrum also accounts for these new additions in the form of a peak at 1742 cm-1 corresponding to the carbonyl of the ester, as well as the presence of two bands at ~620 and 720 cm-1 accounting for the phenyl group. This is a known compound and the data found matches that of the data that was previously reported.29

Synthesis of the azidodeoxy phenacyl diazoester 11 was carried out in a similar manner to that of the DAG phenacyl diazo ester 3. Once again, a method was employed in which p-NBSA acted as an azide source for the diazo transfer, and the base of choice was DBU (Equation 9). The reaction was run under argon atmosphere, overnight, and verified for completion by TLC. The crude product revealed a mixture of product spots and further purification progressed via column chromatography (3:1 / hexane: ethyl 25 acetate), which resulted in azidodeoxy phenacyl diazoester 11 as an orange syrup in 92% yield.

Equation 9.

A key piece of evidence in successful formation of the diazo compound arose from the complete disappearance of the previous 2H signal at 3.65 ppm in the 1H NMR spectrum which depicts the loss of those two protons and their replacement with the diazo species. Another key piece of evidence is also the presence of a large signal at 2089 cm-1 which corresponds to the presence of the diazo group. The presence of the electron- withdrawing diazo group on the molecule also accounts for the resolution of the previous phenyl multiplet into three distinct signals, ranging from 7.22-7.48 respectively. The peak for the alpha carbon in the 13C NMR spectrum at 41.25 ppm has also shifted further downfield due to the presence of the diazo group. This is a known compound and the data found matches that of the data that was previously reported.29

Equation 10. 26

With xylode-derived diazo ester 11 in hand, attempted decomposition could be performed. Azido diazo ester 11 is unique in the fact that it possesses two different nitrogen functional groups. The presence of the azido group allows for the possibility of interference in the C-H insertion process causing the formation of different structures.

Decomposition was attempted utilizing catalytic rhodium tetraacetate (Equation 10) in a nitrogen glove box and subsequent addition of diazo ester 11 via syringe pump. Upon monitoring the reaction via TLC, two spots were found in the product mixture. The reaction was concentrated under reduced pressure and then purified via gradient column chromatography (3:1 / hexanes: ethyl acetate; 3:1 / CH2Cl2: methanol). The higher spot had turned out to be leftover, unreacted diazo starting material (20 mg) while the lower spot provided a complex 1H NMR spectra. Upon referencing previous compounds and their spectra synthesized by Malich, several signals in the 1H NMR spectrum correlated to two of her products, an ether linked dimer and a macrocyclic structure (Figure 10).

While it appeared as though the two products were present in a mixture, they had appreared as a single spot via TLC. Unlike Malich’s previous compounds, 4 new signals were also present in the 1H NMR structure. Utilizing HSQC spectroscopy to compare the

13C and 1H spectra, it was noted that two of the signals, which both appeared as doublets, did not correlate to any of the carbon signals present. The two signals present at 4.3 and

4.5 ppm appear as apparent doublets of triplets as opposed to the anticipated doublet of doublet of doublets and two doublet of doublet signals seem to be appearing further up field, prior to 3.0 ppm. This is interesting to note and of this point, we are unsure as to the exact cause. Their neighboring signals are also not visibly neighbors with any other 27 signal in the spectrum. As of this point however, no successful crystallization has occurred to date. IR has also provided little information indicating the presence of any previously unidentified functional groups.

Figure 10: Structures of the ether-linked dimer and the 14 membered macrocycle

isolated by Malich.

Conclusion

The overall conclusions of the research are reported as follows. Firstly, following completion of all experiments reported in this text, it is important to note that unlike previous synthesis,27 no C-H insertion products of any kind were isolated or characterized. The isolation of the products reported in Malich’s thesis29 were also never successfully isolated. Instead, rather a peculiar and interesting NMR spectrum, supposedly of one product, was obtained showing strange chemical shifts and patterns which allude to the possibility of a mixture of compounds. Finally, the isolation and characterization of azine 4 remains the hallmark reaction of these research efforts. While similar species have been reported, no such reaction had previously occurred in the

Norris lab. This synthesis alone has enlightened me to the real experience of research. 28

Experimental

General Procedure

All reactions were monitored using Thin Layer Chromatography (TLC) and ultraviolet light detection with the reaction materials that are UV-active. A 5% sulfuric acid/methanol solution was used in order to indicate carbohydrate products by charring the material. Purification of products was done using flash column chromatography performed with 32-63 μm, 60-Å silica gel. Bruker Avance II/III 400 MHz NMR instruments with TOPSPIN software were used for 1H, 13C and COSY spectroscopy using CDCl3 as the solvent. All chemical shifts (δ) are recorded in parts per million

(ppm). Multiplet splitting patterns are labeled s (singlet), d (doublet), dd (doublet of doublets), ddd (doublet of doublet of doublets), t (triplet), q (quartet), and m (multiplet) with coupling constants measured in Hertz (Hz). A Thermo Electron Corporation IR 200

Infrared spectrometer was also used for additional analysis of product structure.

Preparation of 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D-glucofuranose (2) from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (1).

To a 500 mL round bottom flask equipped with a magnetic stir bar, diacetone glucose, 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (2.60 g, 1.00 mmol) 1 and phenyl acetic acid (1.50 g, 11.02 mmol) were dissolved in CH2Cl2 (30 mL) and allowed to stir. Once the solution was completely mixed, 4-dimethylamino pyridine, DMAP,

(391.20 mg, 3.20 mmol) was added to the mixture and allowed to dissolve. In a dropwise manner using an addition funnel, 10 mL (6.4 mmol) of 1.0 M N, N’- dicyclohexylcarbodiimide, DCC, in CH2Cl2 was added to the reaction mixture and allowed to stir overnight. Reaction progress was monitored by TLC in 3:1 hexanes: ethyl acetate. The resulting urea byproduct was filtered off and the remaining solution was concentrated under reduced pressure. Ester 2 was recrystallized from hot ethanol, affording a colorless crystalline solid in 69% yield.

1 H NMR (CDCl3): δ 1.26 (s, 3H, CH3), 1.28 (s, 3H, CH3), 1.38 (s, 3H, CH3), 1.50

(s, 3H, CH3), 3.66 (s, 2H, benzyl-CH2), 3.95 (dd, 1H, H-6, J = 5.2 Hz, 8.5 Hz),

3.99 (dd, 1H, H-6’, J = 5.9 Hz, 8.5 Hz), 4.05-4.10 (m, 1H, H-5), 4.18 (dd, 1H, H-

4, J = 3.1 Hz, 7.9 Hz), 4.42 (d, 1H, H-2, J = 3.9 Hz), 5.28 (d, 1H, H-3, J = 2.9

Hz), 5.81 (d, 1H, H-1, J = 3.6 Hz), 7.26-7.32 (m, 5H, phenyl).

13 C NMR (CDCl3): δ 25.17, 26.21, 26.74, 26.77, 41.35, 67.23, 72.31, 76.38,

79.98, 83.28, 105.06, 109.29, 112.31, 127.30 (2x), 128.64 (2x), 129.18, 133.42,

170.04.

M.P.: 62-65 °C 30

IR absorption (selected peaks): 2985.15, 1740.24 cm-1

Preparation of 1,2:5,6-di-O-isopropylidene-3-O-(phenacyldiazo)-α-D-glucofuranose

(3) from 1,2:5,6-di-O-isopropylidene-3-O-phenacyl-α-D-glucofuranose (2).

In a dry 50 mL round-bottom flask equipped with a magnetic stir bar ester 2 (385 mg, 1.02 mmol) and 4-nitrobenzenesulfonyl azide, p-NBSA, (470 mg, 2.06 mmol) were dissolved in acetonitrile (10 mL) and CH2Cl2 (10 mL). The mixture was allowed to stir and DBU (1.2 mL, 8.04 mmol) was added dropwise via syringe. Reaction progress was monitored by TLC using 3:1 hexane:ethyl acetate. Once reaction was determined complete, the resulting mixture was transferred to a separatory funnel, washed with 5%

H2SO4 (3 x 15 mL) and the resulting organic layer was rinsed with deionized H2O (3 x 15 mL). The solution was dried over anhydrous magnesium sulfate and concentrated under reduced pressure to afford crude diazo ester 3, which was then purified by flash column chromatography in a 3:1 hexanes:ethyl acetate system resulting in pure diazo ester 3 (254 mg, 66% yield) as an orange syrup.

1 H NMR (CDCl3): δ 1.26 (s, 6H, 2 x CH3), 1.42 (s, 3H, CH3), 1.54 (s, 3H, CH3),

4.01 (dd, 1H, H-6, J = 4.9 Hz, 8.6 Hz), 4.10 (dd, 1H, H-6’, J = 6.0 Hz, 8.5 Hz),

4.16-4.20 (m, 1H, H-5), 4.27 (dd, 1H, H-4, J = 3.0 HZ, 8.0 Hz), 4.67 (d, 1H, H-2,

J = 3.7 Hz), 5.39 (d, 1H, H-3, J = 3.1 Hz), 5.91 (d, 1H, H-1, J = 3.6 Hz), 7.18-

7.48 (m, 5H, phenyl).

13 C NMR (CDCl3): δ 25.17, 26.21, 26.73, 26.83, 41.36, 67.24, 67.39, 72.55,

77.23, 79.91, 83.46, 105.06, 109.46, 112.36, 124.09, 126.23, 128.65, 129.04,

129.18, 163.77.

M.P.: N/A (syrup)

IR absorption (selected peaks): 2087.15, 1703.24 cm-1

Attempted decomposition of 1,2:5,6-di-O-isopropylidene-3-O-(phenacyldiazo)-α-D- glucofuranose 3.

To an oven-dried 250 mL round-bottom flask equipped with a magnetic stir bar, in a nitrogen glove box (H2O < 0.1 ppm, O2 <0.1 ppm), diazo ester 3 (404 mg, 1.00 mmol) was dissolved in anhydrous CH2Cl2 (20 mL). Rhodium(II) acetate dimer,

Rh2OAc4, (60 mg, 0.14 mmol) was suspended in CH2Cl2 (20 mL) in a separate flask. The

Rh2OAc4 solution was transferred to a 50 mL syringe and the two solutions were added together slowly via syringe pump. Once added, the reaction was allowed to stir for 24 hours while being monitored by TLC 3:1 hexanes:ethyl acetate. Analysis of TLC after 24 hours indicated the presence of two new compounds. Flash column chromatography was used to purify and separate the crude mixture. The two compounds were separated and each had undergone attempts at crystallization in hot ethanol, however, only one product recrystallized. Azine 4 was successfully recrystallized (150 mg, 19% yield) as yellow crystals.

1 H NMR (CDCl3): δ 1.18 (s, 6H, CH3), 1.30 (s, 6H, CH3), 1.45 (s, 6H, CH3), 1.51

(s, 6H, CH3), 3.95 (dd, 2H, H-6, J = 3.9 Hz, 8.6 Hz), 4.02 (dd, 2H, H-6’, J = 5.4

Hz, 8.6 Hz), 4.13-4.23 (m, 4H, H-4, H-5), 4.58 (d, 2H, H-2, J = 3.6 Hz), 5.47 (d,

2H, H-1, J = 3.5 Hz), 5.66 (d, 2H, H-3, J = 2.2 Hz), 7.43 (t, 4H, Ar-H, J = 7.6

Hz), 7.51 (t, 2H, Ar-H, J = 7.3 Hz), 7.85 (d, 4H, Ar-H, J = 8.0 Hz).

13 C NMR (CDCl3): δ 25.15, 25.93, 26.64, 26.71 67.60, 72.19, 77.11, 80.06, 83.29,

105.22, 109.43, 112.43, 127.89 (2x), 128.98 (2x), 130.91, 132.36, 160.37, 163.43.

M:Z calculated: 780 g M:Z found: 819 g (+K) 33

M.P.: 223-226 °C

IR absorption (selected peaks): 2981.80, 1740.80 cm-1

Preparation of 1,2-O-isopropylidene-α-D-xylofuranose (6) and 1,2;3,5-di-O- isopropylidene-α-D-xylofuranose (7) from D-(+)-xylose (5).31

To a 500 mL round-bottom flask equipped with a magnetic stir bar and rubber septum, concentrated sulfuric acid (10.00 mL) was carefully added to acetone (260 mL).

Finely ground D-(+)-xylose (10.00 g, 66.61 mmol) was added slowly and left to stir for approximately 30 minutes until completely dissolved. A 1.1 M solution of Na2CO3 (113 mL, 122.66 mmol) was added slowly while the mixture was cooled in an ice bath and stirred vigorously, After 2.5 hours of vigorous stirring, solid Na2CO3 (7.00 g) was added in the same manner and left to stir for around 24 hours. Additional solid Na2CO3 (7.00 g) was added since the solution was still acidic by litmus paper and allowed to stir for an additional 2 hours. Once the reaction’s pH was found to be basic and consumption of starting material was determined by TLC, the Na2SO4 salts were removed via gravity filtration. The remaining mixture was reduced, dissolved in CH2Cl2, and extracted with

DI H2O (3 x 25 mL). The resulting organic and aqueous layers were concentrated under 34 reduced pressure. The products were then purified via flash column chromatography

(30:1 / CH2Cl2: MeOH). The organic layer contained 1,2;3,5-di-O-isoproylidene-α-D- xylofuranose as a yellow syrup (834 mg), while the aqueous layer contained the monoacetone xylofuranose 6 (7.10 g, 71% yield) as a colorless syrup.

1,2-O-isopropylidene-α-D-xylofuranose (6):

1 H NMR (CDCl3): δ 1.32 (s, 3H, CH3), 1.49 (s, 3H, CH3), 2.98 (t, 1H, OH, J = 5.9

Hz), 4.00-4.18 (m, 2H, H-5, 5’), 4.09 (s, 1H, OH), 4.17 (d, 1H, H-4, J = 3.0 Hz),

4.32 (s, 1H, H-3), 4.52 (d, 1H, H-2, J = 3.5 Hz), 5.98 (d, 1H, H-1, J = 3.5 Hz).

13 C NMR (CDCl3): δ 26.17, 26.77, 61.21, 77.02, 78.67, 85.69, 104.89, 111.82.

M.P.: 66- 67 °C

IR absorption (selected peaks): 3437.31, 2981.97 cm-1

1,2;3,5-di-O-isopropylidene-α-D-xylofuranose (7):

1 H NMR (CDCl3): δ 1.33 (s, 3H, CH3), 1.39 (s, 3H, CH3), 1.44 (s, 3H, CH3), 1.49

(s, 3H, CH3), 4.02-4.03 (m, 1H, H-5’), 4.07 (s, 1H, H-5), 4.11 (dd, 1H, H-4, J =

2.3, 13.6 Hz), 4.29 (d, 1H, H-3, J = 2.3 Hz), 4.52 (d, 1H, H-2, J = 3.6 Hz), 6.00

(d, 1H, H-1, J = 3.6 Hz).

M.P.: N/A (syrup) 35

Preparation of 5-O-(4-methylbenzenesulfonyl)-1,2-O-isopropylidene-α-D-xylofuranose (8) from 1,2-O-isopropylidene-α-D-xylofuranose (6).

In an oven-dried 250 mL round bottom flask equipped with a septum and magnetic stir bar, 1,2-O-isopropylidene-α-D-xylofuranose 6 (5.02 g, 26.4 mmol) was dissolved in pyridine (15 mL) and purged under inert atmosphere. p-Toluenesulfonyl chloride (5.03 g, 26.4 mmol) was added slowly to the reaction mixture via solid addition funnel while the reaction mixture was cooled in an ice/acetone bath. The reaction was allowed to stir for 2.5 hours following addition and was monitored by TLC (ethyl acetate). CH2Cl2 (20 mL) was added to the solution and the result mixture was transferred to a 250 mL separatory funnel where the organic layer was washed with 5% H2SO4 (3 x

25 mL) and deionized H2O (3 x 25 mL). The resulting organic layer was dried with anhydrous magnesium sulfate and concentrated under reduced pressure which resulted in the formation of compound 8 as a white solid, which was recrystallized to yield solid colorless crystals (8.04 g, 89 % yield).

1 H NMR (CDCl3): δ 1.30 (s, 3H, CH3), 1.46 (s, 3H, CH3), 2.21 (d, 1H, -OH, J =

4.9 Hz), 2.45 (s, 3H, benzyl-CH3), 4.10-4.16 (m, 1H, H-4), 4.30-4.35 (m, 3H, H-

3, H-5, H-5’), 4.51 (d, 1H, H-2, J = 3.4 Hz), 5.87 (d, 1H, H-1, J = 3.4 Hz), 7.36

(d, 2H, aryl-H, J = 8.0 Hz), 7.80 (d, 2H, aryl-H, J = 8.0 Hz).

13 C NMR (CDCl3): δ 21.65, 26.20, 26.79, 66.04, 74.32, 77.60, 85.05, 104.98,

112.15, 128.02, 130.00, 132.43, 145.29.

M.P.: 72-75 °C

IR absorption (selected peaks): 3524.21, 2982.40, 814.72 cm-1

Preparation of 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose (9) from 5-O-

(4-methylbenzenesulfonyl)-1,2-O-isopropylidene-α-D-xylofuranose (8).

In a three-neck round bottom flask equipped with a magnetic stir bar, 5.01 g

(14.54 mmol) of 5-O-(4-methylbenzenesulfonyl)-1,2-O-isopropylidene-α-D-xylofuranose

8 was dissolved in 25 mL of dimethylformamide (DMF). Sodium azide (11.5 g, 178 37 mmol) was added and the reaction was heated to 70 °C using a heating mantle. The mixture was stirred overnight (24 hours) while a reflux condenser sat atop the flask. Once determined complete by TLC, the mixture was transferred to a 250 mL separatory funnel using 25 mL CH2Cl2 and 25 mL dI H2O. After extraction with dI H2O (3x 50 mL), the resulting organic layer was dried over anhydrous magnesium sulfate, and reduced to a colorless syrup. The syrup was purified via column chromatography (3:1 / hexane: ethyl acteate) and yielded 750 mg (3.94 mmol, 27%) of a white solid identified as azide 9.

1 H NMR (CDCl3): δ 1.32 (s, 3H, CH3), 1.50 (s, 3H, CH3), 2.15 (d, 1H, -OH, J =

5.12 Hz), 3.59 (dd, 1H, H-5, J = 5.8, 12.9 Hz), 3.64 (dd, 1H, H-5’, J = 6.5, 12.9

Hz), 4.24 - 4.27 (m, 1H, H-3), 4.27-4.30 (m, 1H, H-4), 4.52 (d, 1H, H-2, J = 3.6

Hz) 5.95 (d, 1H, H-1, J = 3.5 Hz).

13 C NMR (CDCl3): δ 26.20, 26.76, 49.24, 75.41, 78.22, 85.37, 104.83, 112.02.

M.P.: 66-69 °C

IR absorption (selected peaks): 3460.88, 2983.85, 2100.48 cm-1

Preparation of 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose (10) from 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose (9).

To a 100 mL round-bottom flask equipped with a septum and magnetic stir bar was added 5-azidodeoxy-1,2-O-isopropylidene-α-D-xylofuranose 9 (500 mg, 2.325 mmol), phenylacetic acid (379 mg, 2.79 mmol) and DMAP (200 mg, 1.63 mmol). The flask was placed under argon atmosphere and anhydrous CH2Cl2 (20 mL) was added via syringe. Into the addition funnel, 10 mL of DCC (1M in CH2Cl2) was added dropwise over two hours. The reaction was allowed to stir overnight (24 h) after which completion was verified by TLC. The resulting mixture was cooled in an ice bath to allow urea byproduct to precipitate out. The urea was removed via gravity filtration and the resulting mixture was transferred to a separatory funnel where it was washed with 5% H2SO4 (3 x

50 mL) and dI H2O (3 x 50 mL). The resulting organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Further purification was carried out via column chromatography (3:1 / hexanes: ethyl acetate), resulting in 512 mg

(1.54 mmol, 66%) of a colorless syrup of azidodeoxy ester 10.

1 H NMR (CDCl3): δ 1.29 (s, 3H, CH3), 1.50 (s, 3H, CH3), 3.25 (dd, 1H, H-5’, J =

5.6, 12.7 Hz), 3.33 (dd, 1H, H-5, J = 6.8, 12.7 Hz), 3.65 (s, 2H, CH2), 4.34-4.37 39

(m, 1H, H-4), 4.46 (d, 1H, H-2, J = 3.4 Hz), 5.21 (d, 1H, H-2, J = 2.2 Hz), 5.88

(d, 1H, H-1, J = 3.3 Hz).

13 C NMR (CDCl3): δ 26.22, 26.70, 41.25, 48.98, 76.45, 77.66, 83.33, 104.77,

112.41, 127.51, 128.77 (2x), 129.18 (2x), 133.17, 170.22.

M.P.: N/A (syrup)

IR absorption (selected peaks): 2983.95, 2098.25, 1742.52 cm-1

Preparation of 3-O-(2-Diazo-2-phenylacetyl)-5-azidodeoxy-1,2-O-isopropylidene-α-

D-xylofuranose (11) from 3-O-(2-phenylacetyl)-5-azidodeoxy-1,2-O-isopropylidene-

α-D-xylofuranose (10).

To a 100 mL round-bottom flask equipped with a magnetic stir bar and septum was added 250 mg (0.75 mmol) ester 10 and p-NBSA (250 mg, 1.09 mmol). Following a purge with argon atmosphere, anhydrous CH2Cl2 (10 mL) was added. DBU (1.0 mL, 6.69 mmol) was added dropwise via syringe over 1 h and the reaction was allowed to stir overnight. Once verified by TLC, the reaction mixture was transferred to a separatory 40

funnel and worked up with 5% H2SO4 (2 x 25 mL) and dI H2O (2 x 25 mL). The resulting organic layer was concentrated under reduced pressure, and then further purified via column chromatography (3:1 / hexanes: ethyl acetate). Purification yielded 260 mg (0.72 mmol, 92%) of diazo ester 11 as an orange syrup.

1 H NMR (CDCl3): δ 1.36 (s, 3H, CH3), 1.57 (s, 3H, CH3), 3.49 (dd, 1H, H-5’, J =

5.6, 12.8 Hz), 3.55 (dd, 1H, H-5, J = 6.8, 12.8 Hz), 4.50 (ddd, 1H, H-4, J = 3.0,

6.0, 6.4 Hz), 4.69 (d, 1H, H-2, J = 3.7 Hz), 5.40 (d, 1H, H-3, J = 3.0 Hz), 5.99 (d,

1H, H-1, J = 3.7 Hz), 7.22-7.28 (m, 1H, Ph), 7.39-7.44 (m, 2H, Ph), 7.47-7.48 (m,

2H, Ph).

13 C NMR (CDCl3): δ 26.23, 26.70, 49.31, 76.87, 77.73, 83.51, 104.78, 112.48,

124.12 (2x), 124.54, 126.39, 129.11 (2x), 163.65.

M.P.: N/A (syrup)

IR absorption (selected peaks): 2983.15, 2089.44, 1701.36 cm-1

Attempted decomposition of 3-O-(2-Diazo-2-phenylacetyl)-5-azidodeoxy-1,2-O- isopropylidene-α-D-xylofuranose (11).

To an oven dried 250 mL round-bottom flask equipped with a magnetic stir bar, in a nitrogen glove box (H2O < 0.1 ppm, O2 <0.1 ppm), rhodium tetraacetate (500 mg,

0.11 mmol) was dissolved in anhydrous CH2Cl2 (100 mL). In a 20 mL scintillation vial, diazo ester 11 (250 mg, 0.69 mmol) was also dissolved in anhydrous CH2Cl2 (15 mL).

The mixture was transferred to a 100 mL round-bottom flask and an additional 5 mL of

CH2Cl2 was added. The two flasks were then removed from the glove box. The solution containing diazo ester 11 was transferred to a 50 mL syringe, which was placed in a syringe pump. Diazo ester 11 was added to the flask containing the rhodium tetraacetate dropwise at a rate of 1 mL/h for 20 hours. Following the addition of the solutions, the mixture was concentrated under reduced pressure, dissolved in CH2Cl2 and purified via gradient column chromatography (3:1 / hexanes: ethyl acetate, 3:1/ CH2Cl2: methanol) resulting in the elution of two spots. The first as an orange syrup (20 mg) which proved to be MAX diazo ester 11, and the second as a colorless syrup (70 mg). Attempts to recrystallize are currently underway.

1 H NMR (CDCl3): δ 1.23 (s, 3H, CH3), 1.31 (s, 3H, CH3), 1.48 (s, 3H, CH3), 1.50

(s, 3H, CH3), 2.74 (dd, 1H, J = 7.0, 12.6 Hz), 2.95 (dd, 1H, J = 6.1, 12.6 Hz), 3.28

(1H, J = 5.6 Hz), 3.38 (1H, J = 5.4), 3.45 (dd, 1H, J = 5.8, 12.7 Hz), 3.51 (dd, 1H,

J = 6.6, 12.8 Hz), 4.12-4.13 (m, 1H), 4.25 (dt, 1H, J = 2.9, 6.6), 4.39 (dt, 1H, J = 42

2.9, 6.1 Hz), 4.55 (d, 1H, J = 3.7 Hz), 5.18 (d, 1H, J = 2.0 Hz), 5.24 (dd, 2H, J =

3.2, 4.4 Hz), 5.66 (d, 1H, 3.6 Hz), 5.91 (d, 1H, J = 3.6), 7.34-7.43 (m, 10H).

13 C NMR (CDCl3): δ 26.19, 26.22, 26.62, 26.68, 48.23, 49.03, 60.38, 72.87,

73.06, 77.22, 77.50, 77.59, 82.87, 83.17, 104.66, 104.77, 112.59, 112.62, 126.33,

126.60, 127.40, 128.68, 128.83, 128.89, 129.12, 137.61, 137.78, 172.58.

M.P.: N/A (syrup)

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Appendix

NMR, IR, Mass Spectra and X-Ray Crystallography

2 (

glucofuranose - D - α -

phenacyl - O - 3 -

isopropylidene

- O - di -

1,2:5,6

H NMR spectrum of H NMR spectrum 1

11: Figure

2 (

glucofuranose - D - α -

phenacyl - O -

3 -

isopropylidene - O - di -

1,2:5,6

C NMR spectrum of C NMR spectrum

12: Figure

). 2 (

glucofuranose - D

- α - phenacyl

- O - 3 -

isopropylidene - O

- di -

1,2:5,6

COSY NMR spectrum of COSY NMR spectrum

Figure 13: Figure

). 2 (

glucofuranose - D - α - phenacyl

- O - 3 -

isopropylidene - O

- di -

1,2:5,6

IR spectrum spectrum of IR

Figure 14: Figure

). 3 (

glucofuranose - D -

α -

yldiazo)

phenac (

- O - 3 -

isopropylidene - O

- di -

1,2:5,6

H NMR spectrum of spectrum H NMR 1

Figure 15: Figure

). 3 (

glucofuranose - D - α

yldiazo)

phenac (

- O - 3 -

isopropylidene - O

- di -

1,2:5,6

C NMR spectrum of C NMR spectrum 13

16: Figure 54

3 (

glucofuranose - D - α -

yldiazo)

phenac ( - O

- 3 -

isopropylidene - O - di -

1,2:5,6

spectrum of IR

17: Figure

). 4

(

glucofuranose -

D - α -

diylidene) -

1,2 -

(phenacylhydrazine -

O - 3 -

isopropylidene - O -

di -

1,2:5,6

of spectrum H NMR 1

Figure 18: Figure 56

). 4 (

glucofuranose - D

- α -

diylidene) - 1,2

(phenacylhydrazine - O

- 3 -

isopropylidene - O - di

1,2:5,6

of C NMR spectrum 13

Figure 19: Figure 57

). 4 (

glucofuranose - D -

α -

diylidene)

- 1,2 -

(phenacylhydrazine - O -

3 -

isopropylidene - O - di -

1,2:5,6

COSY NMR spectrum of COSY NMR spectrum

Figure 20: Figure 58

). 4 (

glucofuranose - D - α

diylidene) - 1,2 -

(phenacylhydrazine - O - 3

isopropylidene -

O - di -

1,2:5,6

IR spectrum spectrum of IR

Figure 21: Figure 59

). 4 ( glucofuranose - D - α - diylidene) - 1,2 - (phenacylhydrazine - O - 3 - isopropylidene - O - di - 1,2:5,6 Mass spectrumMass of

Figure 22: Figure 60

6 (

xylofuranose - D

- α -

isopropylidene - O -

1,2

H NMR spectrum of spectrum H NMR

23: Figure

). 6

(

xylofuranose - D

- α -

isopropylidene - O -

1,2

of C NMR spectrum 13

Figure 24: Figure

). 6 (

xylofuranose - D - α

isopropylidene - O -

1,2

IR spectrum spectrum of IR

Figure 25: Figure

) 7

xylofuranose (

- D - α -

isopropylidene - O

- di -

1,2;3,5

spectrum of spectrum

H NM 1

Figure 26: Figure

). 8

xylofuranose ( xylofuranose - D - α -

isopropylidene - O - 1,2 -

methylbenzenesulfonyl) - (4 - O -

spectrum of spectrum

H NM 1

27: Figure

xylofuranose ( xylofuranose -

D - α -

isopropylidene - O - 1,2 -

methylbenzenesulfonyl) - (4 - O -

spectrum of spectrum

C NM 13

28: Figure

). 8

xylofuranose ( xylofuranose - D - α -

isopropylidene

- O -

1,2 -

methylbenzenesulfonyl) - (4

- O - 5

spectrum of spectrum

COSY NM

Figure 29: Figure

). 8

xylofuranose ( xylofuranose - D - α -

isopropylidene

- O -

1,2 -

methylbenzenesulfonyl) - (4

- O - 5

spectrum of spectrum

COSY NM

Figure 30: Figure

). 9 (

xylofuranose - D -

α -

isopropylidene - O - 1,2

azidodeoxy - 5

spectrum of spectrum

H NM 1

Figure 31: Figure

). 9 (

xylofuranose - D -

α -

isopropylidene - O - 1,2

azidodeoxy - 5

spectrum of spectrum

C NM 3 1

Figure 32: Figure

). 9 (

xylofuranose

- D - α -

isopropylidene - O

- 1,2 -

azidodeoxy - 5

spectrum of spectrum

COSY NM

33: Figure

). 9 (

xylofuranose - D - α -

isopropylidene - O - 1,2 -

azidodeoxy - 5

spectrum spectrum of

Figure 34: Figure

. ) 10 xylofuranose ( xylofuranose - D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 - phenylacetyl) - (2 - O - 3 spectrum of spectrum

R H NM 1

Figure 35: Figure 73

. ) 10 xylofuranose ( xylofuranose - D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 - phenylacetyl) - (2 - O - 3 C NMR spectrum of C NMR spectrum 13

Figure 36: Figure 74

. ) 10 xylofuranose ( xylofuranose - D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 - phenylacetyl) - (2 - O - 3 COSY NMR spectrum of COSY NMR spectrum

Figure 37: Figure 75

. ) 10 xylofuranose ( - D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 - phenylacetyl) - (2 - O - 3 IR spectrum spectrum of IR

Figure 38: Figure 76

- D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 -

). 11 (

phenylacetyl) - 2 - xylofuranose Diazo - (2 - O - 3 spectrum of spectrum

R H NM 1

Figure 39: Figure 77

- D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 -

). 11 (

phenylacetyl) - 2 - xylofuranose Diazo - (2 - O - 3 of

pectrum C NMR s 13 Figure 40: Figure 78

- D - α - isopropylidene - O - 1,2 - azidodeoxy - 5 -

). 11 (

phenylacetyl) - 2 - xylofuranose Diazo - (2 - O - 3 of

pectrum C NMR s 13 Figure 41: Figure 79

. 11 of decomposition product of MAX diazo ester of MAX product of decomposition

pectrum NMR s

H 1 Figure 42: Figure 80

. 11 of decomposition product of MAX diazo ester of MAX product of decomposition

pectrum C NMR s 13 Figure 43: Figure 81

. 11 of decomposition product of MAX diazo ester diazo ester of MAX product of decomposition pectrum COSY s

Figure 44: Figure 82

. 11 of decomposition product of MAX diazo ester diazo ester of MAX product of decomposition pectrum HSQC s

Figure 45: Figure 83

11. IR spectrum product spectrum of MAX diazo ester of decomposition IR Figure 46: Figure 84

. 4

ray of ray azine crystal structure - X

Figure 47: Figure

Table 1. Experimental details

ML_insertionpdt_a_0m Crystal data

Chemical formula C40H48N2O14

Mr 780.80

Crystal system, space group Monoclinic, P21 Temperature (K) 100 a, b, c (Å) 14.9755 (14), 9.3821 (9), 15.0304 (12) (°) 108.140 (4) V (Å3) 2006.8 (3) Z 2 Radiation type Mo Kα (mm-1) 0.10 Crystal size (mm) 0.20 × 0.20 × 0.20 Data collection Diffractometer Bruker AXS D8 Quest CMOS diffractometer Absorption correction Multi-scan SADABS 2014/5

Tmin, Tmax 0.631, 0.746 No. of measured, independent and 66042, 12145, 11210 observed [I > 2 (I)] reflections

Rint 0.064 -1 (sin / )max (Å ) 0.716 Refinement R[F2 > 2 (F2)], wR(F2), S 0.041, 0.112, 1.05 No. of reflections 12145 No. of parameters 515 No. of restraints 1 H-atom treatment H-atom parameters constrained -3 max, min (e Å ) 0.33, -0.22 Absolute structure Flack x determined using 4763 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons, Flack and 86

Wagner, Acta Cryst. B69 (2013) 249-259). Absolute structure parameter 0.0 (2)

Computer programs: Apex3 v2016.1-0 (Bruker, 2016), SAINT V8.37A (Bruker, 2016), SHELXS97 (Sheldrick, 2008), SHELXL2018/3 (Sheldrick, 2017), SHELXLE Rev909 (Hübschle et al., 2011).

Refinement details: Refined as a 2-component twin by a 180 degree rotation around the direct lattice direction -1 0 1. Application of the twin transformation matrix 0 0 -1, 0 -1 0, -1 0 0 yielded a twin ratio of 0.0942(9).

Table 2: Bond Lengths (Å)

N1—C8A 1.288(3) C20A—H20C 0.9800 N1—N2 1.411(2) O1B—C1B 1.413(3) N2—C8B 1.277(3) O1B—C4B 1.437(3) O1A—C1A 1.416(3) C1B—O2B 1.406(3) O1A—C4A 1.436(3) C1B—C2B 1.551(3) C1A—O2A 1.416(3) C1B—H1B 1.0000 C1A—C2A 1.550(3) O2B—C15B 1.424(3) C1A—H1A 1.0000 C2B—O3B 1.417(3) O2A—C15A 1.430(3) C2B—C3B 1.524(3) C2A—O3A 1.414(3) C2B—H2B 1.0000 C2A—C3A 1.519(3) O3B—C15B 1.434(3) C2A—H2A 1.0000 C3B—O4B 1.446(3) O3A—C15A 1.431(3) C3B—C4B 1.514(3) C3A—O4A 1.452(2) C3B—H3B 1.0000 C3A—C4A 1.517(3) O4B—C7B 1.343(3) C3A—H3A 1.0000 C4B—C5B 1.519(3) O4A—C7A 1.338(3) C4B—H4B 1.0000 C4A—C5A 1.513(3) O5B—C5B 1.430(3) C4A—H4A 1.0000 O5B—C18B 1.437(3) O5A—C5A 1.429(3) C5B—C6B 1.526(3) O5A—C18A 1.442(3) C5B—H5B 1.0000 C5A—C6A 1.522(3) O6B—C18B 1.417(3) C5A—H5A 1.0000 O6B—C6B 1.427(3) O6A—C18A 1.423(3) C6B—H6BA 0.9900 O6A—C6A 1.424(3) C6B—H6BB 0.9900 C6A—H6AA 0.9900 O7B—C7B 1.194(3) C6A—H6AB 0.9900 C7B—C8B 1.520(3) O7A—C7A 1.200(3) C8B—C9B 1.474(3) 87

C7A—C8A 1.509(3) C9B—C10B 1.398(3) C8A—C9A 1.469(3) C9B—C14B 1.403(3) C9A—C10A 1.393(3) C10B—C11B 1.390(3) C9A—C14A 1.400(3) C10B—H10B 0.9500 C10A—C11A 1.390(3) C11B—C12B 1.387(4) C10A—H10A 0.9500 C11B—H11B 0.9500 C11A—C12A 1.385(4) C12B—C13B 1.390(4) C11A—H11A 0.9500 C12B—H12B 0.9500 C12A—C13A 1.388(4) C13B—C14B 1.386(3) C12A—H12A 0.9500 C13B—H13B 0.9500 C13A—C14A 1.392(3) C14B—H14B 0.9500 C13A—H13A 0.9500 C15B—C17B 1.505(3) C14A—H14A 0.9500 C15B—C16B 1.518(4) C15A—C16A 1.502(3) C16B—H16D 0.9800 C15A—C17A 1.529(3) C16B—H16E 0.9800 C16A—H16A 0.9800 C16B—H16F 0.9800 C16A—H16B 0.9800 C17B—H17D 0.9800 C16A—H16C 0.9800 C17B—H17E 0.9800 C17A—H17A 0.9800 C17B—H17F 0.9800 C17A—H17B 0.9800 C18B—C19B 1.515(4) C17A—H17C 0.9800 C18B—C20B 1.519(4) C18A—C19A 1.512(4) C19B—H19D 0.9800 C18A—C20A 1.518(4) C19B—H19E 0.9800 C19A—H19A 0.9800 C19B—H19F 0.9800 C19A—H19B 0.9800 C20B—H20D 0.9800 C19A—H19C 0.9800 C20B—H20E 0.9800 C20A—H20A 0.9800 C20B—H20F 0.9800 C20A—H20B 0.9800

Table 3: Bond Angles (°)

C8A—N1—N2 110.15(18) H20B—C20A—H20C 109.5 C8B—N2—N1 112.81(19) C1B—O1B—C4B 106.91(17) C1A—O1A—C4A 108.04(16) O2B—C1B—O1B 110.68(19) O1A—C1A—O2A 110.72(18) O2B—C1B—C2B 104.55(18) O1A—C1A—C2A 107.32(17) O1B—C1B—C2B 107.02(18) O2A—C1A—C2A 104.16(17) O2B—C1B—H1B 111.4 O1A—C1A—H1A 111.4 O1B—C1B—H1B 111.4 O2A—C1A—H1A 111.4 C2B—C1B—H1B 111.4 C2A—C1A—H1A 111.4 C1B—O2B—C15B 110.36(18) C1A—O2A—C15A 107.76(16) O3B—C2B—C3B 107.70(18) O3A—C2A—C3A 109.43(17) O3B—C2B—C1B 104.43(17) O3A—C2A—C1A 104.32(16) C3B—C2B—C1B 103.32(18) C3A—C2A—C1A 103.48(16) O3B—C2B—H2B 113.5 O3A—C2A—H2A 113.0 C3B—C2B—H2B 113.5 C3A—C2A—H2A 113.0 C1B—C2B—H2B 113.5 88

C1A—C2A—H2A 113.0 C2B—O3B—C15B 108.24(17) C2A—O3A—C15A 105.69(16) O4B—C3B—C4B 107.51(18) O4A—C3A—C4A 107.14(16) O4B—C3B—C2B 109.33(17) O4A—C3A—C2A 106.64(16) C4B—C3B—C2B 101.79(18) C4A—C3A—C2A 102.66(16) O4B—C3B—H3B 112.5 O4A—C3A—H3A 113.2 C4B—C3B—H3B 112.5 C4A—C3A—H3A 113.2 C2B—C3B—H3B 112.5 C2A—C3A—H3A 113.2 C7B—O4B—C3B 115.82(17) C7A—O4A—C3A 116.48(16) O1B—C4B—C3B 103.66(17) O1A—C4A—C5A 108.11(17) O1B—C4B—C5B 109.50(18) O1A—C4A—C3A 104.26(16) C3B—C4B—C5B 117.46(19) C5A—C4A—C3A 115.20(17) O1B—C4B—H4B 108.6 O1A—C4A—H4A 109.7 C3B—C4B—H4B 108.6 C5A—C4A—H4A 109.7 C5B—C4B—H4B 108.6 C3A—C4A—H4A 109.7 C5B—O5B—C18B 108.54(19) C5A—O5A—C18A 107.94(18) O5B—C5B—C4B 107.71(19) O5A—C5A—C4A 107.59(18) O5B—C5B—C6B 104.02(19) O5A—C5A—C6A 103.08(18) C4B—C5B—C6B 111.7(2) C4A—C5A—C6A 114.96(18) O5B—C5B—H5B 111.1 O5A—C5A—H5A 110.3 C4B—C5B—H5B 111.1 C4A—C5A—H5A 110.3 C6B—C5B—H5B 111.1 C6A—C5A—H5A 110.3 C18B—O6B—C6B 105.58(19) C18A—O6A—C6A 106.72(18) O6B—C6B—C5B 102.2(2) O6A—C6A—C5A 101.99(18) O6B—C6B—H6BA 111.3 O6A—C6A—H6AA 111.4 C5B—C6B—H6BA 111.3 C5A—C6A—H6AA 111.4 O6B—C6B—H6BB 111.3 O6A—C6A—H6AB 111.4 C5B—C6B—H6BB 111.3 C5A—C6A—H6AB 111.4 H6BA—C6B—H6BB 109.2 H6AA—C6A—H6AB 109.2 O7B—C7B—O4B 126.2(2) O7A—C7A—O4A 125.5(2) O7B—C7B—C8B 124.5(2) O7A—C7A—C8A 124.4(2) O4B—C7B—C8B 109.28(19) O4A—C7A—C8A 110.12(18) N2—C8B—C9B 120.0(2) N1—C8A—C9A 122.75(19) N2—C8B—C7B 121.44(19) N1—C8A—C7A 120.00(18) C9B—C8B—C7B 118.58(19) C9A—C8A—C7A 117.25(18) C10B—C9B—C14B 119.7(2) C10A—C9A—C14A 119.8(2) C10B—C9B—C8B 120.9(2) C10A—C9A—C8A 119.79(19) C14B—C9B—C8B 119.4(2) C14A—C9A—C8A 120.4(2) C11B—C10B—C9B 120.0(2) C11A—C10A—C9A 120.3(2) C11B—C10B—H10B 120.0 C11A—C10A—H10A 119.8 C9B—C10B—H10B 120.0 C9A—C10A—H10A 119.8 C12B—C11B—C10B 120.1(2) C12A—C11A—C10A 119.7(2) C12B—C11B—H11B 119.9 C12A—C11A—H11A 120.1 C10B—C11B—H11B 119.9 C10A—C11A—H11A 120.1 C11B—C12B—C13B 120.1(2) C11A—C12A—C13A 120.5(2) C11B—C12B—H12B 119.9 C11A—C12A—H12A 119.8 C13B—C12B—H12B 119.9 89

C13A—C12A—H12A 119.8 C14B—C13B—C12B 120.4(2) C12A—C13A—C14A 120.2(2) C14B—C13B—H13B 119.8 C12A—C13A—H13A 119.9 C12B—C13B—H13B 119.8 C14A—C13A—H13A 119.9 C13B—C14B—C9B 119.7(2) C13A—C14A—C9A 119.5(2) C13B—C14B—H14B 120.1 C13A—C14A—H14A 120.3 C9B—C14B—H14B 120.1 C9A—C14A—H14A 120.3 O2B—C15B—O3B 104.81(18) O2A—C15A—O3A 103.96(16) O2B—C15B—C17B 108.9(2) O2A—C15A—C16A 109.2(2) O3B—C15B—C17B 108.3(2) O3A—C15A—C16A 109.1(2) O2B—C15B—C16B 110.7(2) O2A—C15A—C17A 110.8(2) O3B—C15B—C16B 110.2(2) O3A—C15A—C17A 110.05(18) C17B—C15B—C16B 113.5(2) C16A—C15A—C17A 113.4(2) C15B—C16B—H16D 109.5 C15A—C16A—H16A 109.5 C15B—C16B—H16E 109.5 C15A—C16A—H16B 109.5 H16D—C16B—H16E 109.5 H16A—C16A—H16B 109.5 C15B—C16B—H16F 109.5 C15A—C16A—H16C 109.5 H16D—C16B—H16F 109.5 H16A—C16A—H16C 109.5 H16E—C16B—H16F 109.5 H16B—C16A—H16C 109.5 C15B—C17B—H17D 109.5 C15A—C17A—H17A 109.5 C15B—C17B—H17E 109.5 C15A—C17A—H17B 109.5 H17D—C17B—H17E 109.5 H17A—C17A—H17B 109.5 C15B—C17B—H17F 109.5 C15A—C17A—H17C 109.5 H17D—C17B—H17F 109.5 H17A—C17A—H17C 109.5 H17E—C17B—H17F 109.5 H17B—C17A—H17C 109.5 O6B—C18B—O5B 105.33(19) O6A—C18A—O5A 106.66(19) O6B—C18B—C19B 108.6(2) O6A—C18A—C19A 111.7(2) O5B—C18B—C19B 109.1(2) O5A—C18A—C19A 108.7(2) O6B—C18B—C20B 110.9(2) O6A—C18A—C20A 108.3(2) O5B—C18B—C20B 110.0(2) O5A—C18A—C20A 109.6(2) C19B—C18B—C20B 112.6(2) C19A—C18A—C20A 111.8(2) C18B—C19B—H19D 109.5 C18A—C19A—H19A 109.5 C18B—C19B—H19E 109.5 C18A—C19A—H19B 109.5 H19D—C19B—H19E 109.5 H19A—C19A—H19B 109.5 C18B—C19B—H19F 109.5 C18A—C19A—H19C 109.5 H19D—C19B—H19F 109.5 H19A—C19A—H19C 109.5 H19E—C19B—H19F 109.5 H19B—C19A—H19C 109.5 C18B—C20B—H20D 109.5 C18A—C20A—H20A 109.5 C18B—C20B—H20E 109.5 C18A—C20A—H20B 109.5 H20D—C20B—H20E 109.5 H20A—C20A—H20B 109.5 C18B—C20B—H20F 109.5 C18A—C20A—H20C 109.5 H20D—C20B—H20F 109.5 H20A—C20A—H20C 109.5 H20E—C20B—H20F 109.5

Table 4: Torsion Angles (°)

C8A—N1—N2—C8B -173.5(2) C4B—O1B—C1B—O2B 90.4(2) 90

C4A—O1A—C1A—O2A 94.3(2) C4B—O1B—C1B—C2B -23.0(2) C4A—O1A—C1A—C2A -18.8(2) O1B—C1B—O2B—C15B -124.7(2) O1A—C1A—O2A—C15A -130.33 C2B—C1B—O2B—C15B -9.8(3) C2A—C1A—O2A—C15A -15.3(2) O2B—C1B—C2B—O3B -7.8(2) O1A—C1A—C2A—O3A 109.26(18) O1B—C1B—C2B—O3B 109.7(2) O2A—C1A—C2A—O3A -8.2(2) O2B—C1B—C2B—C3B -120.36(19) O1A—C1A—C2A—C3A -5.2(2) O1B—C1B—C2B—C3B -2.9(2) O2A—C1A—C2A—C3A -122.65(18) C3B—C2B—O3B—C15B 131.77(19) C3A—C2A—O3A—C15A 138.63(18) C1B—C2B—O3B—C15B 22.4(2) C1A—C2A—O3A—C15A 28.4(2) O3B—C2B—C3B—O4B 162.07(17) O3A—C2A—C3A—O4A 162.14(16) C1B—C2B—C3B—O4B -87.8(2) C1A—C2A—C3A—O4A -87.12(18) O3B—C2B—C3B—C4B -84.4(2) O3A—C2A—C3A—C4A -85.38(19) C1B—C2B—C3B—C4B 25.7(2) C1A—C2A—C3A—C4A 25.4(2) C4B—C3B—O4B—C7B 159.71(18) C4A—C3A—O4A—C7A 157.70(17) C2B—C3B—O4B—C7B -90.6(2) C2A—C3A—O4A—C7A -92.9(2) C1B—O1B—C4B—C3B 40.2(2) C1A—O1A—C4A—C5A 158.52(17) C1B—O1B—C4B—C5B 166.27(18) C1A—O1A—C4A—C3A 35.5(2) O4B—C3B—C4B—O1B 74.5(2) O4A—C3A—C4A—O1A 74.75(19) C2B—C3B—C4B—O1B -40.3(2) C2A—C3A—C4A—O1A -37.4(2) O4B—C3B—C4B—C5B -46.4(2) O4A—C3A—C4A—C5A -43.5(2) C2B—C3B—C4B—C5B -161.21(19) C2A—C3A—C4A—C5A -155.66(18) C18B—O5B—C5B—C4B -112.2(2) C18A—O5A—C5A—C4A -143.47 C18B—O5B—C5B—C6B 6.5(3) C18A—O5A—C5A—C6A -21.6(2) O1B—C4B—C5B—O5B -179.65(18) O1A—C4A—C5A—O5A 179.83(17) C3B—C4B—C5B—O5B -61.8(3) C3A—C4A—C5A—O5A -64.1(2) O1B—C4B—C5B—C6B 66.7(3) O1A—C4A—C5A—C6A 65.7(2) C3B—C4B—C5B—C6B -175.5(2) C3A—C4A—C5A—C6A -178.22(19) C18B—O6B—C6B—C5B 37.8(2) C18A—O6A—C6A—C5A -35.5(2) O5B—C5B—C6B—O6B -26.8(3) O5A—C5A—C6A—O6A 34.8(2) C4B—C5B—C6B—O6B 89.1(2) C4A—C5A—C6A—O6A 151.59(19) C3B—O4B—C7B—O7B 1.5(3) C3A—O4A—C7A—O7A -6.5(3) C3B—O4B—C7B—C8B 179.71(17) C3A—O4A—C7A—C8A 175.07(16) N1—N2—C8B—C9B -179.2(2) N2—N1—C8A—C9A -176.2(2) N1—N2—C8B—C7B 0.0(3) N2—N1—C8A—C7A 3.5(3) O7B—C7B—C8B—N2 -97.2(3) O7A—C7A—C8A—N1 86.8(3) O4B—C7B—C8B—N2 84.5(3) O4A—C7A—C8A—N1 -94.7(2) O7B—C7B—C8B—C9B 82.0(3) O7A—C7A—C8A—C9A -93.5(3) O4B—C7B—C8B—C9B -96.2(2) O4A—C7A—C8A—C9A 85.0(2) N2—C8B—C9B—C10B 159.2(2) N1—C8A—C9A—C10A -176.2(2) C7B—C8B—C9B—C10B -20.1(3) C7A—C8A—C9A—C10A 4.1(3) N2—C8B—C9B—C14B -19.8(3) N1—C8A—C9A—C14A 6.0(4) C7B—C8B—C9B—C14B 160.9(2) C7A—C8A—C9A—C14A -173.7(2) C14B—C9B—C10B—C11B 1.4(4) C14A—C9A—C10A—C11A -0.9(4) C8B—C9B—C10B—C11B -177.6(2) C8A—C9A—C10A—C11A -178.7(2) C9B—C10B—C11B—C12B -0.7(4) C9A—C10A—C11A—C12A 1.5(4) C10B—C11B—C12B—C13B -0.3(4) 91

C10A—C11A—C12A—C13A -0.4(4) C11B—C12B—C13B—C14B 0.6(4) C11A—C12A—C13A—C14A -1.1(4) C12B—C13B—C14B—C9B 0.1(4) C12A—C13A—C14A—C9A 1.6(4) C10B—C9B—C14B—C13B -1.1(4) C10A—C9A—C14A—C13A -0.6(4) C8B—C9B—C14B—C13B 177.9(2) C8A—C9A—C14A—C13A 177.2(2) C1B—O2B—C15B—O3B 23.5(3) C1A—O2A—C15A—O3A 33.2(2) C1B—O2B—C15B—C17B 139.3(2) C1A—O2A—C15A—C16A 149.5(2) C1B—O2B—C15B—C16B -95.3(2) C1A—O2A—C15A—C17A -85.0(2) C2B—O3B—C15B—O2B -28.6(2) C2A—O3A—C15A—O2A -38.5(2) C2B—O3B—C15B—C17B -144.7(2) C2A—O3A—C15A—C16A -154.79 C2B—O3B—C15B—C16B 90.5(2) C2A—O3A—C15A—C17A 80.2(2) C6B—O6B—C18B—O5B -34.7(2) C6A—O6A—C18A—O5A 23.1(2) C6B—O6B—C18B—C19B -151.5(2) C6A—O6A—C18A—C19A -95.5(2) C6B—O6B—C18B—C20B 84.3(2) C6A—O6A—C18A—C20A 140.9(2) C5B—O5B—C18B—O6B 16.6(3) C5A—O5A—C18A—O6A 0.3(2) C5B—O5B—C18B—C19B 133.1(2) C5A—O5A—C18A—C19A 120.9(2) C5B—O5B—C18B—C20B -102.9(2) C5A—O5A—C18A—C20A -116.7(2)