Development of the Conjugate Addition/Nitro-Mannich Reaction
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Abstract Multicomponent Reactions of Salicylaldehyde, Cyclic Ketones, and Arylamines Through Cooperative Enamine-Metal Lewis
ABSTRACT MULTICOMPONENT REACTIONS OF SALICYLALDEHYDE, CYCLIC KETONES, AND ARYLAMINES THROUGH COOPERATIVE ENAMINE-METAL LEWIS ACID CATALYSIS by Ryan Gregory Sarkisian Multicomponent reactions (MCRs) are the most atom economic, highly selective, and convergent type of reaction. This allows for a reaction to have a wide scope and allows for maximization of the complexity of a product. Catalyzing these MCRs with asymmetric catalysis is a novel way to introduce stereocontrol into highly complex molecules with various functional groups. Asymmetric catalysis is considered the most efficient method for constructing highly functionalized optically active stereopure compounds. There are three pillars of asymmetric catalysis: biocatalysis, transition metal catalysis, and organocatalysis. This research focuses on two of these pillars, transition metal catalysis and organocatalysis, working cooperatively to catalyze this MCR. The focus is to educate or refresh the audience on the basic topics that make up the complexity of the MCRs being catalyzed by cooperative asymmetric catalysis. Ultimately to explore the cooperative catalysts used to synthesize both the racemic and asymmetric three fused ring products (9-((4-methoxyphenyl)amino)-2,3,4,4a,9,9a-hexahydro-1H-xanthen-4a-ol). MULTICOMPONENT REACTIONS OF SALICYLALDEHYDE, CYCLIC KETONES, AND ARYLAMINES THROUGH COOPERATIVE ENAMINE-METAL LEWIS ACID CATALYSIS A THESIS Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Science Department of -
Catalytic Direct Asymmetric Michael Reactions
ORGANIC LETTERS 2001 Catalytic Direct Asymmetric Michael Vol. 3, No. 23 Reactions: Taming Naked Aldehyde 3737-3740 Donors Juan M. Betancort and Carlos F. Barbas III* The Skaggs Institute for Chemical Biology and the Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037 [email protected] Received September 5, 2001 ABSTRACT Direct catalytic enantio- and diastereoselective Michael addition reactions of unmodified aldehydes to nitro olefins using (S)-2-(morpholinomethyl)- pyrrolidine as a catalyst are described. The reactions proceed in good yield (up to 96%) in a highly syn-selective manner (up to 98:2) with enantioselectivities approaching 80%. The resulting γ-formyl nitro compounds are readily converted to chiral, nonracemic 3,4-disubstituted pyrrolidines. The Michael reaction is generally regarded as one of the Typically, carbon nucleophiles that contain an active most efficient carbon-carbon bond forming reactions, and methylene center such as malonic acid esters, â-keto esters, studies concerning this reaction have played an important nitroalkanes, etc. have been studied in the Michael reaction. role in the development of modern synthetic organic Carbonyl compounds, and ketones in particular, have gener- chemistry.1 As the demand for optically active compounds ally only been used as donors following their preactivation has soared in recent years, much progress has been made in by conversion into a more reactive species such as enol or the development of asymmetric variants of this reaction, enamine equivalents.5,6 In these cases, additional synthetic providing for the preparation of Michael adducts with high enantiomeric purity.2 Though remarkable advances have been (3) (a) Chataigner, I.; Gennari, C.; Ongeri, S.; Piarulli, U.; Ceccarelli, S. -
Copyrighted Material
Index Abbreviations receptor sites 202, 211 weak 122 amino acids, Table 500–1 muscarinic 413 weak, pH calculation 147–8 nucleic acids 551 nicotinic 413 Acid–base nucleotides, Table 551 as quaternary ammonium salt 202 catalysis, enzymes 516 peptides and proteins 504 Acetylcholinesterase equilibria 121 phosphates and diphosphates 277 enzyme mechanism 519–21 interactions, predicting 155–7 structural, Table 14 hydrolysis of acetylcholine 279 Acidic reagents, Table 157 ACE (angiotensin-converting enzyme) inhibitors 279 Acidity enzyme action 532 Acetyl-CoA carboxylase, in fatty acid acidity constant 122 inhibitors 532 biosynthesis 595 bond energy effects 125 Acetal Acetyl-CoA (acetyl coenzyme A) definition 121 in etoposide 233 as acylating agent 262 electronegativity effects 125 formation 229 carboxylation to malonyl-CoA 595, hybridization effects 128 polysaccharides as polyacetals 232 609 inductive effects 125–7 as protecting group 230 Claisen reaction 381 influence of electronic and structural Acetal and ketal enolate anions 373 features 125–34 cyclic, as protecting groups 481 in Krebs cycle 585 and leaving groups, Table 189 groups in sucrose 231 from β-oxidation of fatty acids 388 pKa values 122–5 Acetaldehyde, basicity 139 as thioester 262, 373 resonance / delocalization effects 129–34 Acetamide, basicity 139 Acetylene, bonding molecular orbitals 31 Acidity (compounds) Acetaminophen, see paracetamol Acetylenes, acidity 128 acetone 130 Acetoacetyl-CoA, biosynthesis from N-Acetylgalactosamine, in blood group acetonitrile 365 acetyl-CoA 392 -
Comparative Total Syntheses of Strychnine
Comparative Total Syntheses of Strychnine N C D MacMillan Group Meeting N H O H A H B E Nathan Jui H N N H H F G July 22, 2009 O O O References: Pre-Volhardt: Bonjoch Chem. Rev. 2000, 3455. Woodward Tetrahedron, 1963, 247. Volhardt J. Am. Chem. Soc. 2001, 9324. Magnus J. Am. Chem. Soc. 1993, 8116. Martin J. Am. Chem. Soc. 2001, 8003. Overman J. Am. Chem. Soc. 1995, 5776. Bodwell Angew. Chem. Int. Ed. 2002, 3261. Kuehne J. Org. Chem. 1993, 7490. Mori J. Am. Chem. Soc. 2003, 9801. Kuehne J. Org. Chem. 1998, 9427. Shibasaki Tetrahedron 2004, 9569. Rawal J. Org. Chem. 1994, 2685. Fukuyama J. Am. Chem. Soc. 2004, 10246. Bosch, Bonjoch Chem. Eur. J. 2000, 655. Padwa Org. Lett. 2007, 279. History and Structure of (!)-Strychnine ! Isolated in pure form in 1818 (Pelletier and Caventou) ! Structural Determination in 1947 (Robinson and Leuchs) ! 24 skeletal atoms (C21H22N2O2) ! Isolated in pure form in 1818 (Pelletier and Caventou) N ! Over !25 07 -pruinbglisc,a 6ti-osntesr epoecrteaninteinrgs to structure ! Structural Determination in 1947 (Robinson and Leuchs) ! Notor!io u Ss ptoirxoicne (nletethr a(lC d-o7s) e ~10-50 mg / adult) N H H ! Over 250 publications pertaining to structure O O ! Comm!o nClyD uEs eridn gr osdyesntet mpoison ! Notorious poison (lethal dose ~10-50 mg / adult) ! Hydroxyethylidine Strychnos nux vomica ! $20.20 / 10 g (Aldrich), ~1.5 wt% (seeds), ~1% (blossoms) "For it's molecular size it is the most complex substance known." -Robert Robinson History and Structure of (!)-Strychnine ! 24 skeletal atoms (C21H22N2O2) N ! 7-rings, 6-stereocenters ! Spirocenter (C-7) N H H O O ! CDE ring system ! Hydroxyethylidine "For it's molecular size it is the most complex substance known." -Robert Robinson "If we can't make strychnine, we'll take strychnine" -R. -
Chem 345 Pset 22 Key 1.) for Aldol, Michael, Claisen, and Mannich
Chem 345 PSet 22 Key 1.) For Aldol, Michael, Claisen, and Mannich reactions, the first step is the creation of a nucleophile. Under basic conditions, the nucleophile is an enolate. Under acidic conditions, the nucleophile is an enol. Draw the mechanism for the formation of both species and then draw the reaction backwards. O NaOH O H H O HCl OH H H 2.) In the case of a Mannich reaction, the electrophile (an imine) must also be made. Draw the mechanism for the forward and backward reaction: O MeNH2 N H H cat. AcOH H H 3.) When a secondary amine is used and the carbonyl has an enolizable proton, an enamine can be formed. Are enamines nucleophilic or electrophilic? Nucleophilic H O N N H2O H cat. AcOH H enamine N N H H enamine 4.) The following reaction is the Lobry-de-Bruyn-von-Ekenstein reaction. Don’t worry about the name. I only recently found out that that was the official name for the rearrangement leading from glucose to fructose or mannose and back again. I was taught it under a different name: the Carbohydrate Game. Under acidic or basic conditions, it is possible that the following sugars (glucose, fructose, and mannose) are in equilibrium with each other. Draw the acid catalyzed version and the base catalyzed version. (Hint: this is just a repeat of question 1.) O O H H H2C OH + + HO H H3O H OH H3O O or or HO- HO- HO H HO H HO H H OH H OH H OH H OH H OH H OH H2C OH H2C OH H2C OH D-glucose D-fructose D-mannose O O H H H2C OH + + HO H H3O H OH H3O O or or HO- HO- HO H HO H HO H H OH H OH H OH H OH H OH H OH H2C OH H2C OH H2C OH D-glucose D-fructose D-mannose The sugars are drawn in a Fisher projection (or what I think of is a dead cat projection). -
Heterocyclic Chemistrychemistry
HeterocyclicHeterocyclic ChemistryChemistry Professor J. Stephen Clark Room C4-04 Email: [email protected] 2011 –2012 1 http://www.chem.gla.ac.uk/staff/stephenc/UndergraduateTeaching.html Recommended Reading • Heterocyclic Chemistry – J. A. Joule, K. Mills and G. F. Smith • Heterocyclic Chemistry (Oxford Primer Series) – T. Gilchrist • Aromatic Heterocyclic Chemistry – D. T. Davies 2 Course Summary Introduction • Definition of terms and classification of heterocycles • Functional group chemistry: imines, enamines, acetals, enols, and sulfur-containing groups Intermediates used for the construction of aromatic heterocycles • Synthesis of aromatic heterocycles • Carbon–heteroatom bond formation and choice of oxidation state • Examples of commonly used strategies for heterocycle synthesis Pyridines • General properties, electronic structure • Synthesis of pyridines • Electrophilic substitution of pyridines • Nucleophilic substitution of pyridines • Metallation of pyridines Pyridine derivatives • Structure and reactivity of oxy-pyridines, alkyl pyridines, pyridinium salts, and pyridine N-oxides Quinolines and isoquinolines • General properties and reactivity compared to pyridine • Electrophilic and nucleophilic substitution quinolines and isoquinolines 3 • General methods used for the synthesis of quinolines and isoquinolines Course Summary (cont) Five-membered aromatic heterocycles • General properties, structure and reactivity of pyrroles, furans and thiophenes • Methods and strategies for the synthesis of five-membered heteroaromatics -
Mannich Reaction
1. Introduction 1.1- Mannich Reaction The Mannich reaction is three component condensation in which a compound containing an active hydrogen atom is allowed to react with formaldehyde and an NH-amine derivative . Secondary amines rather than primary amines and ammonia are employed , the resulting product (Mannich Base ) is an amine compound having the N atom linked to the R substrate through a methylene group 1,2. The aminoalkylation of CH-acidic compounds was described by several authors as early as the 19th. century. However, it was Carl Mannich who was the first to recognize the enormous significance of this reaction , and it was he who extended the chemistry into a broad based synthetic methodology through systematic research. Since then this reaction that now carries his name has developed into one of the most important C-C bond-forming reactions in organic chemistry3,4. The Mannich reaction is a classical method for the preparation of β -aminoketones and aldehydes (Mannich bases) and, as such, is one of the most important basic reaction types in organic chemistry. It is the key step in the synthesis of numerous pharmaceuticals and natural products3,4. 1 The Mannich reaction can be presented by the following equation: The essential feature of the reaction is the replacement of the active hydrogen atom by an aminomethyl or substituted aminomethyl group. The symbolizes the active hydrogen component which includes ketones, aldehydes, acids, esters, phenols, acetylenes, picolines, nitroalkanes and quinolines1,2. 1.2- Mechanism of the Mannich reaction The mechanism of the Mannich reaction has been well investigated, the condensation reaction occurs in two steps: first, the amine reacts with formaldehyde to give condensation product (5 ), (6), ( 7) (step I) which then attacks the substrate R-H (step II) .The reaction does not normally follow the other possible route (step III and IV) ; however, some successful reaction between hydroxymethyl derivatives (8) and alkylamines to give Mannich bases (9) should be mentioned . -
Recoverable Phospha-Michael Additions Catalyzed by a 4-N,N
molecules Article Recoverable Phospha-Michael Additions Catalyzed by a 4-N,N-Dimethylaminopyridinium Saccharinate Salt or a Fluorous Long-Chained Pyridine: Two Types of Reusable Base Catalysts Eskedar Tessema 1,†, Vijayanath Elakkat 1,† , Chiao-Fan Chiu 2,3,*, Jing-Hung Zheng 1, Ka Long Chan 1, Chia-Rui Shen 4,5, Peng Zhang 6,* and Norman Lu 1,7,* 1 Institute of Organic and Polymeric Materials, National Taipei University of Technology, Taipei 106, Taiwan; [email protected] (E.T.); [email protected] (V.E.); [email protected] (J.-H.Z.); [email protected] (K.L.C.) 2 Department of Pediatrics, Linkou Medical Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan 3 Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan 4 Department of Medical Biotechnology and Laboratory Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; [email protected] 5 Department of Ophthalmology, Linkou Medical Center, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan 6 Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221-0172, USA 7 Development Center for Smart Textile, National Taipei University of Technology, Taipei 106, Taiwan Citation: Tessema, E.; Elakkat, V.; * Correspondence: [email protected] (C.-F.C.); [email protected] (P.Z.); Chiu, C.-F.; Zheng, J.-H.; Chan, K.L.; [email protected] (N.L.) Shen, C.-R.; Zhang, P.; Lu, N. † These authors contributed equally to this work. Recoverable Phospha-Michael Additions Catalyzed by a Abstract: Phospha-Michael addition, which is the addition reaction of a phosphorus-based nucle- 4-N,N-Dimethylaminopyridinium ophile to an acceptor-substituted unsaturated bond, certainly represents one of the most versatile and Saccharinate Salt or a Fluorous powerful tools for the formation of P-C bonds, since many different electrophiles and P nucleophiles Long-Chained Pyridine: Two Types can be combined with each other. -
Development of the Interrupted Nazarov Cyclization of Allenyl Vinyl Ketones, with Application to the Total Synthesis of the Cyclooctane Natural Product Roseadione
Development of the Interrupted Nazarov Cyclization of Allenyl Vinyl Ketones, with Application to the Total Synthesis of the Cyclooctane Natural Product Roseadione by Vanessa M. Marx Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Dalhousie University Halifax, Nova Scotia May 2011 © Copyright by Vanessa M. Marx, 2011 DALHOUSIE UNIVERSITY DEPARTMENT OF CHEMISTRY The undersigned hereby certify that they have read and recommend to the Faculty of Graduate Studies for acceptance a thesis entitled “Development of the Interrupted Nazarov Cyclization of Allenyl Vinyl Ketones, with Application to the Total Synthesis of the Cyclooctane Natural Product Roseadione” by Vanessa M. Marx in partial fulfilment of the requirements for the degree of Doctor of Philosophy. Dated: May 19, 2011 Supervisor: _________________________________ Readers: _________________________________ _________________________________ _________________________________ Departmental Representative: _________________________________ ii DALHOUSIE UNIVERSITY DATE: May 19, 2011 AUTHOR: Vanessa M. Marx TITLE: Development of the Interrupted Nazarov Cyclization of Allenyl Vinyl Ketones, with Application to the Total Synthesis of the Cyclooctane Natural Product Roseadione DEPARTMENT OR SCHOOL: Department of Chemistry DEGREE: PhD CONVOCATION: October YEAR: 2011 Permission is herewith granted to Dalhousie University to circulate and to have copied for non-commercial purposes, at its discretion, the above title upon the request of individuals or institutions. I understand that my thesis will be electronically available to the public. The author reserves other publication rights, and neither the thesis nor extensive extracts from it may be printed or otherwise reproduced without the author’s written permission. The author attests that permission has been obtained for the use of any copyrighted material appearing in the thesis (other than the brief excerpts requiring only proper acknowledgement in scholarly writing), and that all such use is clearly acknowledged. -
Electron Deficient Heterocycle. Examples Abound
Pyridines Pyridines are the most commonly encountered π- electron deficient heterocycle. Examples abound. H O 4 N nifedipine 5 3 N NH2 (anti- angina) H CH3 6 2 MeO2C CO2Me N N 1 N NO2 nicotine niacin (nicitinamide) (in NADP) There are many classical syntheses of pyridines; only a few can be covered in the time available. 1. Hantzsch Synthesis Probably the conceptually simples pyridine synthesis would be a simple extension based on the Paal- Knorr pyrrole synthesis. In other words…. Paal-Knorr NH3 R5 R2 5 2 R N R OO H the shouldn't a 1,5-dicarbonyl do.... NH3 [O] 6 2 6 2 R R 6 2 R N R O O R N R H This is absolutely feasible. Furthermore, as you might expect, the 1,5-dicarbonyls are readily accessible by Michael reaction chemistry (1,4-, conjugate additions). The one- pot version of this, where the unsaturated carbonyl is prepared, the Michael reaction occurs, and the pyridine formation is accomplished, is quite common. It is called the Hantzsch synthesis. 4 O O 4 R O NH3 or O R O EtO2C CO2Et R4 NH4OAc EtO + + OEt EtO OEt ∆∆∆ H2O, O O O O OO ** R4 R4 FeCl3 EtO2C CO2Et EtO2C CO2Et ∆∆∆ H2O, N N H It’s rather forceful conditions, but the ester groups can be decarboxylated. The shown example is a symmetric case, but unsymmetrical ones can be done by doing the aldol condensation (here called a Knoevenagel) first, discretely, and then putting that compound (** ) into a separate reaction doing the subsequent steps. -
Enantioselective Total Synthesis of (-)-Strychnine1 Scheme1
J. Am. Chem. SOC.1993,115, 9293-9294 9293 Enantioselective Total Synthesis of (-)-Strychnine1 Scheme1 Steven D. Knight, Larry E. Overman,' and Garry Pairaudeau Department of Chemistry University of California Imine, California 9271 7-2025 Received July 8, 1993 OTlPS Strychnine (1) has played a vital role in the development of d h,i natural productschemistry. First isolated in 1818 fromstrychnos ignatii by Pelletier and Caventou, strychnine was among the first plant alkaloids obtained in pure form. After decades of inves- OBU' (-)-Strychnine(1) tigation, the structural elucidation of strychnine in 1946 repre- sented one of the crowning accomplishments of classical structural chemistry.394 Its total synthesis by Woodward only 8 years later was an achievement of even greater significance, since prior to this feat no compound approaching the complexity of strychnine ,oms had been prepared by chemical synthesis.* That strychnine's P' seven rings displayed on only 24 skeletal atoms still represents a formidable challenge for total synthesis is apparent in the fact that only last year was a second total synthesis of strychnine published by Magnus and co-workers.6 This synthesis, like the pioneering Woodward synthesis, involved intersection with an intermediate available by degradation of stry~hnine.~.~Most recently, two syntheses of (*)-strychnine have been communicated by the groups of Stork' and Kuehne.* Herein we report the first asymmetric total synthesis of (-)-strychnine. This highly efficient total synthesis features the use of the cationic aza-Cope-Mannich reaction to assemble the pentacyclic strychnan c~re.~J~ The preparation in enantiopure form of the unsaturated azabicyclo[3.2. -
Approach and Synthesis of Strychnos Alkaloids
N° d'ordre : 4155 THÈSE Présentée à L'UNIVERSITÉ BORDEAUX I ÉCOLE DOCTORALE DES SCIENCES CHIMIQUES par Dawood Hosni DAWOOD POUR OBTENIR LE GRADE DE DOCTEUR SPÉCIALITÉ : CHIMIE ORGANIQUE ********************* TOWARDS THE SYNTHESIS OF MONOTERPENOIDS INDOLE ALKALOIDS OF THE ASPIDOSPERMATAN AND STRYCHNAN TYPE ********************* Soutenue le: 17 décembre 2010 Après avis de: MM. PIVA Olivier Professeur, Claude Bernard Lyon 1 Rapporteur PALE Patrick Professeur, Louis Pasteur Strasbourg 1 Rapporteur Devant la commission d'examen formée de : MM. PIVA Olivier Professeur, Claude Bernard Lyon 1 Rapporteur PALE Patrick Professeur, Louis Pasteur Strasbourg 1 Rapporteur POISSON Jean-François Chargé de recherche, CNRS Examinateur VINCENT Jean-Marc Directeur de recherche, CNRS Examinateur LANDAIS Yannick Professeur, Bordeaux 1 Directeur de thèse ROBERT Frédéric Chargé de recherche, CNRS Codirecteur de thèse - 2010 - Abbreviations ∆: reflux °C: celsius degrees Ac: acetyle ALB Aluminium Lithium bis(binaphthoxide) complex AIBN : azobis(isobutyronitrile) aq.: aqueous Ar : aromatic BINAP : 2,2'-bis(diphenylphosphino)-1,1'-binaphthyle BINAPO : 2-diphenylphosphino-2'-diphenylphosphinyl-1,1'-binaphthalene BINOL: 1,1’-bi-2-naphthol Boc: tert-butyloxycarbonyle BOX: Bisoxazoline Bz : benzoyle Bn: benzyle cat. : catalytic DBU: 1,8-diazabicyclo[5.4.0]undec-7-ene DCM: dichloromethane DCC: dicyclohexacarbodiimide dr.: diastereomeric ratio DIBAL-H: diisobutylaluminium hydride DIPEA: diisopropyléthylamine (Hünig Base) DMAP: dimethylaminopyridine DME: dimethoxyethane