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Rhodium-Catalyzed Decomposition of Carbohydrate Diazo Esters By Rhodium-Catalyzed Decomposition of Carbohydrate Diazo Esters by 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. iv 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! vi 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
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