ISCHIA ADVANCED SCHOOL OF ORGANIC CHEMISTRY
|
|
- Alexandrina Bradford
- 5 years ago
- Views:
Transcription
1 ewis acid activation ewis base activation ISCIA ADVACED SC F GAIC CEMISTY Dual in Enantioselective Synthesis of Cyanohydrins Me A A Me UM ewis base catalysis is the process by which an electronpair donor increases the rate of a given reaction by interacting with an acceptor atom in one of the reagents or substrates. The binding event may enhance either the electrophilic or nucleophilic character of the bound species. Furthermore, the ewis base should not be consumed or altered during the course of the reaction - a hallmark of any catalytic process. S.E. Denmark and G.. Beutner, Angew. Chem. Int. Ed. 2008, 47, Christina Moberg M Si Si Enhanced electrophilicity at Si Biocatalysis Synthetic systems ewis or Brønsted base B 2 2 Asp i i ys B Asp i ys 2 2 i C 2 3 ewis acid rate enhancement: Shibasaki, M.; Kanai, M. Chem. arm. Bull. 2001, 49, Kanemasa, S.; Ito, K. Eur. J. rg. Chem. 2004, Ma, J.-A.; Cahard, D. Angew. Chem. Int. Ed. 2004, 43, Kanai, M.; Kato,.; Ichikawa, E.; Shibasaki, M. Synlett 2005,
2 Early examples Enzyme catalysis rganocatalysis Corey s oxazaborolidine oyori s dialkylzinc P 2- is 3 is Zn 2 is F 3 C CF 3 S Chiral Scaffold Base u 2 B B Me Me 2 Zn Zn C 2 "M" C F Carbohydrate elongation C (C) n C 2 C 1. C 2. (C) n C 2 The adiponitrile process C C C
3 TMS as cyanide source ther sources first prepared in 1782 by C. W. Scheele Versatile synthetic route to cyanohydrins known for more than 100 years First asymmetric cyanation made by osenthaler in 1908 Metal catalysts affording highly enantioenriched products known today Mowry, D. T., Chem. ev. 1948, 42, 189 osenthaler,., Biochem. Z. 1908, 14, 238 orth, M., Tetrahedron: Asymmetry, 2003, 14, 147 Brunel, J.-M.; olmes, I. P. Angew. Chem. Int. Ed. 2004, 43, 2752 Carl Wilhelm Scheele ( ) Easy to handle in lab TMS-protected cyanohydrins prepared directly, prevents racemization: - abile - Expensive - Volatile, highly toxic and flammable TMS Et 4 - Me P Me Me P Me Me Me ewis acid catalysis--salen catalyst Base Catalysed Additons to Ketones Et 2 equiv. 1 mol% catalyst -40 C 18 h 100% conv. 95% ee Et atural and modified cinchona alkaloids Several days reaction times Belokon, Y. ; Blacker, A. J.; Clutterbuck,. A.; orth, M. rg. ett., 2003, 5, 4505 S.-K. an,. Deng, J. Am. Chem. Soc. 2001, 123,
4 Dual P EWIS BASE Et 2 Al Cl Cl Al EWIS ACID P Et 2 Et 5 mol% catalyst -40 C 18 h Et Si Et Will ewis Acid - ewis Base Catalysis increase the reactivity? Y. amashima, D. Sawada, M. Kanai, M. Shibasaki, J. Am. Chem. Soc. 1999, 121, 2641 J. Casas, A. Baeza, J. M. Sansano, C. ájera, J. M. Saá, Tetrahedron: Asymmetry 2003, 14, 197 Et 5 mol% catalyst -40 C Et Et 5 mol% catalyst -40 C Base time (h) yield ee (%) Et 3, 10% Et Base time(h) yield ee(%) DMAP DABC Et Et i Pr Cinchonidine Quinine Sparteine
5 Aldehyde time yield ee (h) isolated (%) Benzaldehyde Pivalaldehyde Valeraldehyde p-me-benzaldehyde p-cl-benzaldehyde t-cinnemaldehyde (,)-Salen- Et 3-40 C Me ()-tembamide Me red C 2 2 Me ()-aegeline traditional indian medicines with hypoglycemic activity? Aegle marmelos. Veum, S.. M. Pereira, J. C. van der Waal, U. anefeld, Eur. J. rg. Chem. 2006, ewis base nucleophile activation ewis Base Dual ewis base electrophile activation ewis Acid * time (h) yield ee (%) 10% DABC Et Sparteine Cinchonidine Sparteine (ent-complex) Cinchonidine (ent-complex) S. undgren, E. Wingstrand, M. Penhoat, C. Moberg, J. Am. Chem. Soc. 2005, 127
6 ewis Base ewis Acid * ewis Base Aldehyde time yield ee (h) isolated (%) (%) Benzaldehyde Pivalaldehyde Valeraldehyde p-me-benzaldehyde p-me-benzaldehyde p-cl-benzaldehyde (E)-cinnemaldehyde % -40 C, 8h yield ee (%) DABC <1 - Et Sparteine 23 0 Cinchonidine 9 40 S. undgren, E. Wingstrand, M. Penhoat, C. Moberg, J. Am. Chem. Soc. 2005, 127, Dual Cl fenvalerate A Duel Amongst ivals Cl Cl cypermethrin A E A E Br Br deltamethrin F 3 C B u B u CF 3 acrinathrin
7 ' esults "", Et 3 ' ' Dual ' * ' Me 75-96% ee, except Cl Increase reactivity of the system Increase selectivty of the system ewis Base ewis Acid igh Throughput Screening ewis Acids ewis Bases Enzymatic method for determining enantiomeric excess A: 50µl B: 50µl ewis Acid ewis Base Absorbance Principle: Selectively process one of the enantiomers of a product mixture from a catalytic reaction A B C: 20 µl S aswell, ull C Channel dimensions of 100*50 µm Flow: 1 µl/ min Pressure driven flow eaction mixture a. Analysis of unreacted benzaldehyde AD AD, AD b. Analysis of (S)--acetylated cyanohydrin ' CAB AD AD, AD c. Analysis of ()--acetylated cyanohydrin ' PE AD AD, AD A S Up to 92% conversion and 80% ee A. amberg, S. undgren, M. Penhoat, C. Moberg, K. ult, J. Am. Chem. Soc. 2006, 128,
8 Additons to Ketones Conclusion Et 3 racemic nonracemic ewis acid-ewis base activation is efficient in cyanations of aldehydes with acetyl cyanide and cyanoformate, providing -functionalized highly enantioenriched cyanohydrins in high yields with perfect atom economy. The conversions and enantioselectivities can be idetermined by an enzymatic high throughput method. ewis Base ' * ewis Acid Activated by Me - racemic Dynamic kinetic resolution '
New Methods for Chiral Cyanohydrin Synthesis
ew Methods for Chiral Cyanohydrin Synthesis Erica Wingstrand Doctoral Thesis Stockholm 2009 Akademisk avhandling som med tillstånd av Kungl Tekniska ögskolan i Stockholm framlägges till offentlig granskning
More informationEfficient Synthesis and Analysis of Chiral Cyanohydrins
Efficient Synthesis and Analysis of Chiral Cyanohydrins Stina Lundgren Doctoral Thesis Stockholm 2007 Akademisk avhandling som med tillstånd av Kungliga Tekniska högskolan i Stockholm framlägges till offentlig
More informationStrategies for Catalytic Asymmetric Electrophilic a Halogenation of Carbonyl Compounds
Strategies for Catalytic Asymmetric Electrophilic a alogenation of Carbonyl Compounds 1 2 Y Catalyst [X + ] 1 X! 2 Y intermann, L. ; Togni, A. Angew. Chem. Int. Ed. 2000, 39, 4359 4362 amashima, Y.; Sodeoka,
More informationEnantioenriched cyanohydrin O-phosphates: Synthesis and applications as chiral building blocks*
Pure Appl. Chem., Vol. 79, No. 2, pp. 213 221, 2007. doi:10.1351/pac200779020213 2007 IUPAC Enantioenriched cyanohydrin O-phosphates: Synthesis and applications as chiral building blocks* Alejandro Baeza
More informationMeasuring enzyme (enantio)selectivity
Measuring enzyme (enantio)selectivity Types of selectivity - review stereoisomers Stereoselective synthesis (create) vs. resolutions (separate) Enantioselectivity & enantiomeric purity Ways to measure
More informationBifunctional Asymmetric Catalysts: Design and Applications. Junqi Li CHEM Sep 2010
Bifunctional Asymmetric Catalysts: Design and Applications Junqi Li CHEM 535 27 Sep 2010 Enzyme Catalysis vs Small-Molecule Catalysis Bronsted acid Lewis acid Lewis acid Bronsted base Activation of both
More informationEnantioselective Protonations
Enantioselective Protonations Marc Timo Gieseler 25.02.2013 15.03.2013 Group Seminar AK Kalesse 1 verview Introduction Enantioselective Protonation of Cyclic Substrates Enantioselective Protonation of
More informationAsymmetric Catalysis of Cyanide Addition Reactions Using Metal(Salen) Complexes
Asymmetric Catalysis of Cyanide Addition Reactions Using Metal(Salen) Complexes A thesis submitted for the Degree of Doctor of ilosophy by Courtney M. Williamson ewcastle University September 2010 Contents.
More information"-Amino Acids: Function and Synthesis
"-Amino Acids: Function and Synthesis # Conformations of "-Peptides # Biological Significance # Asymmetric Synthesis Sean Brown MacMillan Group eting ovember 14, 2001 Lead eferences: Cheng,. P.; Gellman,
More informationAsymmetric Catalysis by Lewis Acids and Amines
Asymmetric Catalysis by Lewis Acids and Amines Asymmetric Lewis acid catalysis - Chiral (bisooxazoline) copper (II) complexes - Monodentate Lewis acids: the formyl -bond Amine catalysed reactions Asymmetric
More informationAsymmetric Catalysis by Chiral Hydrogen-Bond Donors
Asymmetric Catalysis by Chiral Hydrogen-Bond Donors Angew. Chem. Int. Ed., 2006, 45, 1520~1543 Mark S. Taylor and Eric N. Jacobsen* Current Literature Presentation Zhenglai Fang Wipf s Group at Pitt Zhenglai
More informationChiral Brønsted Acid Catalysis
Chiral Brønsted Acid Catalysis Aryl Aryl Aryl Aryl S CF 3 2 P Fe CF 3 CF 3 2 Jack Liu ov. 16, 2004 CF 3 Introduction Chiral Brønsted acid catalysis in nature: enzymes and peptides Chiral Brønsted acid
More informationStereodivergent Catalysis. Aragorn Laverny SED Group Meeting July
Stereodivergent Catalysis Aragorn Laverny SED Group Meeting July 31 2018 1 Stereodivergent Catalysis In the context of asymmetric synthesis, a stereodivergent process is one that allows access to any given
More informationStructure. Extremely interesting BPs (very high Tm ~ C) Excellent thermic and mechanical properties
tructure Extremely interesting BPs (very high Tm ~ 220-230 C) Excellent thermic and mechanical properties Limitations: no straigthforward synthetic pathways available (Expensive material) Applications:
More informationi-pr 2 Zn CHO N Sato, I.; Sugie, R.; Matsueda, Y.; Furumura, Y.; Soai, K. Angew. Chem., Int. Ed. Engl. 2004, 43, 4490
Asymmetric Synthesis Utilizing Circularly Polarized Light Mediated by the otoequilibration of Chiral lefins in Conjuction with Asymmetric Autocatalysis l-cpl r-cpl (S) () Sato, I.; Sugie,.; Matsueda, Y.;
More informationChiral Proton Catalysis in Organic Synthesis. Samantha M. Frawley Organic Seminar September 14 th, 2005
Chiral Proton Catalysis in rganic Synthesis Samantha M. Frawley rganic Seminar September 14 th, 2005 Seminar utline Introduction Lewis Acid-assisted Chiral Brønsted Acids Enantioselective protonation for
More informationPlanar-Chiral Phosphine-Olefin Ligands Exploiting a (Cyclopentadienyl)manganese(I) Scaffold to Achieve High Robustness and High Enantioselectivity
Planar-Chiral Phosphine-Olefin Ligands Exploiting a (Cyclopentadienyl)manganese(I) Scaffold to Achieve High Robustness and High Enantioselectivity Reporter: Cong Liu Checker: Hong-Qiang Shen Date: 2017/02/27
More informationFacile preparation of α-amino ketones from oxidative ring-opening of aziridines by pyridine N-oxide
Facile preparation of α-amino ketones from oxidative ring-opening of aziridines by pyridine -oxide rg. Biomol. Chem., 2007, 5, 3428 Luo, Z.-B.; Wu, J.-Y.; ou, X.-L.; Dai, L.-X. Ts toluene Ts 80 o C John
More informationC h a p t e r 1. Enantioselective LUMO-Lowering Organocatalysis. The presentation of the Nobel Prize in 2001 to William S. Knowles, Ryoji Noyori,
1 C h a p t e r 1 Enantioselective LUM-Lowering rganocatalysis. I. Introduction. The presentation of the obel Prize in 2001 to William S. Knowles, Ryoji oyori, and K. Barry Sharpless recognized the influence
More informationDevelopment and Studies of the Processes Involved in Minor Enantiomer Recycling. Anna Laurell Nash
Development and Studies of the Processes Involved in Minor Enantiomer Recycling Anna Laurell Nash Doctoral Thesis Stockholm 2014 Akademisk avhandling som med tillstånd av Kungl Tekniska ögskolan i Stockholm
More informationHalogen Bond Applications in Organic Synthesis. Literature Seminar 2018/7/14 M1 Katsuya Maruyama
Halogen Bond Applications in Organic Synthesis Literature Seminar 2018/7/14 M1 Katsuya Maruyama 1 Contents 1. Introduction 2. Property of Halogen Bond 3. Application to Organic Synthesis 2 1. Introduction
More informationChiral Bronsted Acids as Catalysts
Chiral Bronsted Acids as Catalysts Short Literature Seminar 6/3/08 Dustin aup BIL Derived osphoric Acids - First reported in 1992 as a ligand by irrung and coworkers. 4 h 2 irrung Tet. Lett. 1992, 33,
More informationAsymmetric reactions catalyzed by chiral titanium complexes
Issue in onor of Prof. Zhi-Tang uang AKIVC 2003 (ii) 21-31 Asymmetric reactions catalyzed by chiral titanium complexes Fuxue Chen, b Xiaoming Feng, a * Yaozhong Jiang b a Sichuan Key Laboratory of Green
More informationChiral Supramolecular Catalyst for Asymmetric Reaction
Chiral Supramolecular Catalyst for Asymmetric Reaction 2017/1/21 (Sat.) Literature Seminar Taiki Fujita (B4) 1 Introduction Rational design of chiral ligands remains very difficult. Conventional chiral
More informationAsymmetric Nucleophilic Catalysis
Asymmetric ucleophilic Catalysis Chiral catalyst X 2 Chiral catalyst X = alkyl, X 1 2 1 Vedejs, E.; Daugulis,. J. Am. Chem. Soc. 2003, 125, 4166-4173 Shaw, S. A.; Aleman,.; Vedejs, E. J. Am. Chem. Soc.
More informationLecture 6: Transition-Metal Catalysed C-C Bond Formation
Lecture 6: Transition-Metal Catalysed C-C Bond Formation (a) Asymmetric allylic substitution 1 u - d u (b) Asymmetric eck reaction 2 3 Ar- d (0) Ar 2 3 (c) Asymmetric olefin metathesis alladium π-allyl
More informationElectrophilic Carbenes
Electrophilic Carbenes The reaction of so-called stabilized diazo compounds with late transition metals produces a metal carbene intermediate that is electrophilic. The most common catalysts are Cu(I)
More informationCatalytic Asymmetric [4+1] Annulation of Sulfur Ylides with Copper Allenylidene Intermediates. Reporter: Jie Wang Checker: Shubo Hu Date: 2016/08/02
Catalytic Asymmetric [4+1] Annulation of Sulfur Ylides with Copper Allenylidene Intermediates Reporter: Jie Wang Checker: Shubo Hu Date: 2016/08/02 Xiao, W.-J. et al. J. Am. Chem. Soc. 2016, 138, 8360.
More informationDirect Organocatalytic Enantioselective Mannich Reactions of Ketimines: An Approach to Optically Active Quaternary α-amino Acid Derivatives
Direct rganocatalytic Enantioselective Mannich eactions of Ketimines: An Approach to ptically Active Quaternary α-amino Acid Derivatives Wei Zhang, Steen Saaby, and Karl Anker Jorgensen The Danish ational
More informationStereoselective reactions of the carbonyl group
1 Stereoselective reactions of the carbonyl group We have seen many examples of substrate control in nucleophilic addition to the carbonyl group (Felkin-Ahn & chelation control) If molecule does not contain
More informationChiral Catalysis. Chiral Catalyst. Substrate. Chiral Catalyst
Chiral Catalysis Chiral (stoichiometric) reagents are a very important class of compound but... eed a stoichiometric quantity of the chiral component Unless it is cheap or recoverable this is not very
More informationLewis Base Catalysis: the Aldol Reaction (Scott Denmark) Tom Blaisdell Friday, January 17 th 2014 Topic Talk
Lewis Base Catalysis: the Aldol eaction (Scott Denmark) Tom Blaisdell Friday, January 17 th 2014 Topic Talk Scott E. Denmark 1975 - S.B. in Chemistry MIT (ichard. olm and Daniel S. Kemp) 1980 - D.Sc in
More informationStable gold(iii) catalysts by oxidative addition of a carboncarbon
Stable gold(iii) catalysts by oxidative addition of a carboncarbon bond Chung-Yeh Wu, Takahiro oribe, Christian Borch Jacobsen & F. Dean Toste ature, 517, 449-454 (2015) presented by Ian Crouch Literature
More informationAsymmetric Radical Reactions. Zhen Liu 08/30/2018
Asymmetric adical eactions Zhen Liu 08/30/2018 Contents Introduction eactions Using Chiral Auxiliary Chiral Lewis Acid-diated eactions Transition tal-catalyzed eactions eactions Using Chiral rganocatalysts
More informationChiral Catalyst II. Palladium Catalysed Allylic Displacement ( -allyl complexes) 1. L n Pd(0) 2. Nuc
Chiral Catalyst II ast lecture we looked at asymmetric catalysis for oxidation and reduction Many other organic transformations, this has led to much investigation Today we will look at some others...
More informationThe Novel Application of Chiral -Ethylphenyl Amine Tartaric Acid Salts- Cyanosilylation of Prochiral Aldehydes
The pen Catalysis Journal, 010,, 8791 87 pen Access The Novel Application of Chiral Ethylphenyl Amine Tartaric Acid Salts Cyanosilylation of Prochiral Aldehydes Luo Mei *,1, Zhang Jia ai, Yin ao, Sun Jie
More informationMicroreactors in Chemistry! Christina Moberg!
Microreactors in Chemistry! Christina Moberg! 19th century equipment for synthesis 20th centrury equipment for synthesis Today: high throughput and downsizing Microreactors! Threedimensional structures
More informationLipase mediated kinetic and dynamic kinetic resolution of racemic 2- hydroxy-2-(5-phenylthiophene-2-yl)acetonitrile and its derivatives
Lipase mediated kinetic and dynamic kinetic resolution of racemic 2- hydroxy-2-(5-phenylthiophene-2-yl)acetonitrile and its derivatives Cyanohydrins are versatile building blocks in organic synthesis;
More informationKinetic Resolutions. Some definitions and examples Resolution: A process leading to the separation of enantiomers, or derivatives thereof.
Material outline: For the Scientist in you: Definitions Theoretical treatment Kinetic esolutions General eferences: Vedejs, ACIEE, 2005, 3974 Jacobsen, Adv. Syn. Cat. 2001, 5 Kagan, Topics in Stereochemistry,
More informationDirect Catalytic Aldol Reactions
Direct Catalytic Aldol eactions Shibasakiʼs and Trostʼs contributions toward the development of catalytic enolate reactions. Li Li Ln Li ʻThe time has come,ʼ the Walrus said, ʻTo talk of many things: f
More informationStereoselective reactions of enolates
1 Stereoselective reactions of enolates Chiral auxiliaries are frequently used to allow diastereoselective enolate reactions Possibly the most extensively studied are the Evan s oxazolidinones These are
More informationThe contents of the thesis are arranged in four chapters. Chapter I provides information
ABSTRACT Thesis Title: PEG-400 Activated Synthesis of Substituted 1,2,3-Triazoles, (±)- Cyanoacetates and Enantioselective Synthesis of 2- Allyl (4-tertbutyldimethylsilyloxy)-5-phenyl tetrahydrofuran-3-ol:
More informationEnantioselective Borylations. David Kornfilt Denmark Group Meeting Sept. 14 th 2010
Enantioselective Borylations David Kornfilt Denmark Group Meeting Sept. 14 th 2010 30.000-foot View Enantioenriched Organoboranes What to do with them Crudden C. M. et. al., Eur. J. Org. Chem. 2003, 46
More informationMolybdenum-Catalyzed Asymmetric Allylic Alkylation
Molybdenum-Catalyzed Asymmetric Allylic Alkylation X MoL n u u * Tommy Bui 9/14/04 Asymmetric Allylic Alkylation from a Synthetic Viewpoint X X M u u * and/or u form a C-C bond with the creation of a new
More informationStereoselective Synthesis of Configurationally Stable Functionalized Ethano-Bridged Tröger Bases
Stereoselective Synthesis of Configurationally Stable Functionalized Ethano-Bridged Tröger Bases Michon, C.; Sharma, A.; Bernardinelli, G.; Francotte, E.; Lacour, J. Chem. Commun., 2010, 46, 2206-2208
More informationWhen something goes wrong. Goya: Mother showing her derformed child to two women Louvre, Paris
1 ew Catalytic Asymmestric eactions Karl Anker Jørgensen Danish ational eserach Foundation: Center for Catalysis Department of Chemistry, Aarhus University Denmark kaj@chem.au.dk When something goes wrong
More informationYoung Chemist s Panel - Review Meeting 2012
Asymmetric Nucleophilic Catalysis Young Chemist s Panel - Review Meeting 2012 26th th November 2012 Dr. Dave Carbery, Department of Chemistry, University of Bath Setting the Context Catalysing Acyl Transfer
More informationParallel Kinetic Resolution. Group Meeting Timothy Chang
Parallel Kinetic Resolution (PKR) Group Meeting 09 29 2009 Timothy Chang Vedejs, E.; Chen, X. J. Am. Chem. Soc. 1997, 119, 2584. Tanaka, K.; Fu, G. C. J. Am. Chem. Soc. 2003, 125, 8078. KR versus PKR The
More informationShi Asymmetric Epoxidation
Shi Asymmetric Epoxidation Chiral dioxirane strategy: R 3 + 1 xone, ph 10.5, K 2 C 3, H 2, C R 3 formed in situ catalyst (10-20 mol%) is prepared from D-fructose, and its enantiomer from L-sorbose oxone,
More informationThe Vinylogous Aldol Reaction
The Vinylogous Aldol Reaction Reporter: Sixuan Meng Supervisor: Prof. Huang 2013-09-09 Zanardi, F. et al. Chem. Rev. 2000, 100, 1929 Zanardi, F. et al.. Chem. Rev. 2011, 111, 3076 Introduction 2 3 Regiochemical
More informationMechanistic Implications in the Morita Baylis Hillman Alkylation: Isolation and Characterization of an Intermediate
Mechanistic Implications in the Morita Baylis Hillman Alkylation: Isolation and Characterization of an Intermediate M. E. Krafft,* T. F. N. Haxell, K. A. Seibert, and K. A. Abboud Department of Chemistry
More informationSpiro Monophosphite and Monophosphoramidite Ligand Kit
Spiro Monophosphite and Monophosphoramidite Ligand Kit metals inorganics organometallics catalysts ligands custom synthesis cgm facilities nanomaterials 15-5162 15-5150 15-5156 15-5163 15-5151 15-5157
More informationPolymeric salen-ti(iv) or V(V) complex catalyzed asymmetric synthesis of O-acetylcyanohydrins from KCN, Ac 2 O and aldehydes
Tetrahedron 60 (2004) 10469 10477 Polymeric salen-ti(iv) or V(V) complex catalyzed asymmetric synthesis of O-acetylcyanohydrins from KCN, Ac 2 O and aldehydes Wei Huang, a,b Yuming Song, a Jing Wang, a
More informationPalladium-Catalyzed Asymmetric Benzylic Alkylation Reactions
Palladium-Catalyzed Asymmetric Benzylic Alkylation Reactions Reporter: Hong-Qiang Shen Checker: Cong Liu Date: 2016/07/12 Masahiro Miura et al. Angew. Chem. Int. Ed. 2016, 55, 6973. Masahiro Miura Osaka
More informationChiral Amplification. Literature Talk Fabian Schneider Konstanz, Universität Konstanz
Chiral Amplification Literature Talk Fabian Schneider Konstanz, 18.10.2017 Overview 1) Motivation 2) The nonlinear Effect in asymmetric catalysis - First encounters - Basic principles - Formalization and
More informationThe Hydrolytic Kinetic Resolution Jacobsen s Catalyst
The Hydrolytic Kinetic Resolution Jacobsen s Catalyst CHEM 373 Advanced rganic Lab Kenyon College Yutan Getzler The Hydrolytic Kinetic Resolution Jacobsen s Catalyst by Yutan D. Y L. Getzler is licensed
More informationLewis Base Catalysis in Organic Synthesis
Hu Group Lewis Base Catalysis in Organic Synthesis Group Meeting Yuwen Zeng Sep. 28 th, 2014 Introduction Definitions Basic concepts Presentation Outline Lewis base catalysis: n- * Interactions Electrophilic
More informationUse of Cp 2 TiCl in Synthesis
Use of 2 TiCl in Synthesis eagent Control of adical eactions Jeff Kallemeyn May 21, 2002 eactions of 2 TiCl 1. Pinacol Coupling H H H 2. Epoxide pening H H E H Chemoselectivity Activated aldehydes (aromatic,
More informationCarbonyl Ylide Cycloadditions
Carbonyl Ylide Cycloadditions cond. icholas Anderson Denmark Group eting 07/13/10 Carbonyl Ylides Uncharged 1,3-Dipole Conjugated π-system ighly reactive on-isolable Generate in-situ Carbonyl Ylide Stability
More informationBack to Sugars: Enzymatic Synthesis
Back to Sugars: Enzymatic Synthesis Zhensheng Ding ov. 04 orthrup, A. B.; M acm illan, D. W. C. Science 2004, 305, 1752 orthrup, A. B. and MacMillan, D. W. C. J. Am. Chem. Soc. 2002, 124, 6798-6799 orthrup,
More informationChiral Diol Promoted Boronates Addi3on Reac3ons. Lu Yan Morken Group Boston College
Chiral Diol Promoted Boronates Addi3on Reac3ons Lu Yan Morken Group Boston College Main Idea R R B or R R B Ar * exchange B * * or B Ar R 1 R 1 R 2 R 1 R 2 Products not nucleophilic enough nucleophilic
More informationVI. Metal alkyls from oxidative addition / insertion
V. Metal alkyls from oxidative addition / insertion A. Carbonylation - C insertion very facile, metal acyls easily cleaved, all substrates which undergo oxidative addition can in principle be carbonylated.
More informationNucleophilic Heterocyclic Carbene Catalysis. Nathan Werner Denmark Group Meeting September 22 th, 2009
Nucleophilic Heterocyclic Carbene Catalysis Nathan Werner Denmark Group Meeting September 22 th, 2009 Thiamine Thiamine Vitamin B 1 The first water-soluble vitamin described Is naturally synthesized by
More informationOrganocatalytic Umpolung via N- Heterocyclic Carbenes. Qinghe Liu Hu Group Meeting August 20 th 2015
rganocatalytic Umpolung via N- Heterocyclic Carbenes Qinghe Liu Hu Group Meeting August 20 th 2015 Contents Part 1: Introduction Part 2: N-Heterocyclic carbene-catalyzed umpolung: classical umpolung, conjugated
More informationThe aldol reaction with metal enolates proceeds by a chair-like, pericyclic process: favored. disfavored. favored. disfavored
The aldol reaction with metal enolates proceeds by a chair-like, pericyclic process: Z-enolates: M 2 M 2 syn 2 C 2 favored 2 M 2 anti disfavored E-enolates: M 2 2 C 3 C 3 C 2 favored 2 M M disfavored In
More informationCatalytic Asymmetric Acyl Halide-Aldehyde Cyclocondensation Reactions of Substituted Ketenes
Catalytic Asymmetric Acyl Halide-Aldehyde Cyclocondensation eactions of Substituted Ketenes Scott G. elson, Cheng Zhu, and Xiaoqiang Shen J. Am. Chem Soc. 2004, 126, 14-15. Michael C. Myers, Literature
More informationChapter 4 Functional Group Transformations: Oxidation and Reduction. 4.8 Terminology for Reduction of Carbonyl Compounds
Chapter 4 Functional Group Transformations: Oxidation and Reduction Oxidation states (numbers) Less E.N. than C = -1 More E.N. than C = +1 C = 0 H H H C C OH H H 4.8 Terminology for Reduction of Carbonyl
More informationGraphical Abstract. Asymmetric cyanohydrin synthesis using
This is an author-produced version of the following Elsevier-published article: Belokon, Clegg, Harrington, Young and orth, Asymmetric cyanohydrin synthesis using heterobimetallic catalysts obtained from
More informationCopper-Catalyzed Synthesis of Esters from Ketones. Alkyl Group as a Leaving Group.
Copper-Catalyzed Synthesis of Esters from Ketones. Alkyl Group as a Leaving Group. akatani, Y.; Koizumi, Y.; Yamasaki, R.; Saito, S. rg. Lett. 2008, 10, 2067-2070. An Annulation Reaction for the Synthesis
More informationTotal synthesis of Spongistatin
Literature Semminar 1. Introduction: Total synthesis of Spongistatin Chen Zhihua (M2) Isolation: Pettit et al. J. rg. Chem. 1993, 58, 1302. Kitagawa et al. Tetrahedron Lett. 1993, 34, 1993. Fusetani et
More informationChapter 1. Asymmetric Organocatalysis: New Modes of Chemical Activation
Chapter 1 Asymmetric rganocatalysis: ew Modes of Chemical Activation Introduction The chemical substances that make up living organisms are predominantly chiral and often exist as single enantiomers in
More informationAsymmetric Autocatalysis and the Origin of Homochirality of Biomolecules
Research from Soai s group Asymmetric Autocatalysis and the Origin of Homochirality of Biomolecules Kenso SOAI Department of Applied Chemistry, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo
More informationDepartment of Chemistry, University of Saskatchewan Saskatoon SK S7N 4C9, Canada. Wipf Group. Tyler E. Benedum Current Literature February 26, 2005
Ward, D.E; Jheengut, V.; Akinnusi, O.T. Enantioselective Direct Intermolecular Aldol Reactions with Enantiotopic Group Selectivity and Dynamic Kinetic Resolution, Organic Letters 2005, ASAP. Department
More informationFunctionalization of C(sp 3 ) H Bonds Using a Transient Directing Group
Literature eport Functionalization of C(sp 3 ) Bonds Using a Transient Directing Group eporter: Mu-Wang Chen Checker: Yue Ji Date: 2016-04-05 Yu, J.-Q. et al. Science 2016, 351, 252-256. Scripps esearch
More informationMild Cobalt-Catalyzed Hydrocyanation of Olefins with Tosyl Cyanide
Mild Cobalt-Catalyzed ydrocyanation of lefins with Tosyl Cyanide 1 3 2 + Ts Co cat., Si 3 Et, 1-3 h, T 1 2 3 Gaspar, B.; Carreira, E. M. Angew. Chem. Int. Ed. ASAP Current Literature Kalyani Patil 12 May
More informationRacemic catalysis through asymmetric activation*
Pure Appl. Chem., Vol. 73, No. 2, pp. 255 259, 2001. 2001 IUPAC Racemic catalysis through asymmetric activation* Koichi Mikami, Toshinobu Korenaga, Yousuke Matsumoto, Makoto Ueki, Masahiro Terada, and
More informationChapter 14. Principles of Catalysis
Organometallics Study Meeting 2011/08/28 Kimura Chapter 14. Principles of Catalysis 14. 1. General Principles 14.1.1. Definition of a Catalyst 14.1.2. Energetics of Catalysis 14.1.3. Reaction Coordinate
More informationA Highly Efficient Organocatalyst for Direct Aldol Reactions of Ketones and Aldehydes
A ighly Efficient rganocatalyst for Direct Aldol Reactions of Ketones and Aldehydes Zhuo Tang, Zhi-ua Yang, Xiao-ua Chen, Lin-Feng Cun, Ai-Qiao Mi, Yao-Zhong Jiang, and Liu-Zhu Gong Contribution from the
More informationAsymmetric Alklylation of Enolates
Asymmetric Alklylation of Enolates M with material from A G Meyers http://faculty.chemistry.harvard.edu/myers/pages/chem-215-handouts 745 rganic Synthesis Spring 2015 Asymmetric Alkylation - eed to control
More informationAsymmetric Deprotonation
( )-sparteine i-pr, t 2, -98 C 84% ee Asymmetric Deprotonation gands, Bases, and Applications CF 3 TMS t-bu TMSCl, MPA TF, -100 C t-bu 93% ee Fe (i-pr) 2 1. n-bu ( )-sparteine t 2, -78 C 2. 2 PCl P 2 Fe
More informationDual enantioselective control by heterocycles of (S)-indoline derivatives*
Pure Appl. Chem., Vol. 77, No. 12, pp. 2053 2059, 2005. DOI: 10.1351/pac200577122053 2005 IUPAC Dual enantioselective control by heterocycles of (S)-indoline derivatives* Yong Hae Kim, Doo Young Jung,
More informationAsymmetric Lewis Base Strategies for Heterocycle Synthesis
Asymmetric Lewis Base trategies for eterocycle ynthesis Dr Andrew mith EatCEM, chool of Chemistry, University of t Andrews 1st cottish-japanese ymposium of rganic Chemistry, University of Glasgow Friday
More informationSupporting Information
Supporting Information Wiley-VCH 2008 69451 Weinheim, Germany Supporting Information for Chiral Brönsted Acid Catalyzed Asymmetric Baeyer-Villiger Reaction of 3-Substituted Cyclobutanones Using Aqueous
More informationNon-Linear Effects in Asymmetric Catalysis: A Useful Tool in Understanding Reaction Mechanisms. Group Meeting Aaron Bailey 12 May 2009
Non-Linear Effects in Asymmetric Catalysis: A Useful Tool in Understanding Reaction chanisms Group eting Aaron Bailey 12 May 2009 What is a Non-Linear Effect? In asymmetric catalysis, the ee (er) of the
More informationResearch in our group encompasses the following 4 areas in Synthetic Organic Chemistry.
Research in our group encompasses the following 4 areas in Synthetic Organic Chemistry. 1] Development of Asymmetric Catalysis 2] Total Synthesis of Natural products 3] Development of Novel Protecting-Group-Free
More informationConstruction of Chiral Tetrahydro-β-Carbolines: Asymmetric Pictet Spengler Reaction of Indolyl Dihydropyridines
Literature Report V Construction of Chiral Tetrahydro-β-Carbolines: Asymmetric Pictet Spengler Reaction of Indolyl Dihydropyridines Reporter Checker Date : Xiao-Yong Zhai : Xin-Wei Wang : 2018-04-02 You,
More informationKeisuke Suzuki. Baran lab Group Meeting 6/11/16. Shigenobu Umemiya. Akira Suzuki. Takanori Suzuki (Hokkaido University)
197.D., Teruaki Mukaiyama, University of Tokyo 193 Assistant Professor, Keio University 197 Lecturer, Keio University 199 Assocate Professor, Keio University 1990 Visiting Professor, ET 1994 ull Professor,
More informationShort Literature Presentation 10/4/2010 Erika A. Crane
Copper-Catalyzed Enantioselective Synthesis of trans-1- Alkyl-2-substituted Cyclopropanes via Tandem Conjugate Additions-Intramolecular Enolate Trapping artog, T. D.; Rudolph, A.; Macia B.; Minnaard, A.
More informationMidterm Exam #1 /310 CHEM 6352 Fall 2012
Midterm Exam #1 /310 CEM 6352 Fall 2012 ( %) Name ct 5 th, 2012 18:30-21:00 You may NT use any references or aids to complete the following with the exception of a chemical model set and the scrap paper
More informationWilkinson s other (ruthenium) catalyst
Wilkinson s other (ruthenium) catalyst Cl 3 ; 2 h 3, reflux 3h h 3 Cl h 3 h Cl 3 Good catalyst especially for 2 1-alkenes 2, base toluene Cl h 3 h 3 h 3 Et 3 Cl h 3 Cl h 3 h 3 R h 3 h 3 Cl h 3 R RC 2 C
More informationC H Activated Trifluoromethylation
Literature report C H Activated Trifluoromethylation Reporter:Yan Fang Superior:Prof. Yong Huang Jun. 17 th 2013 Contents Background Trifluoromethylation of sp-hybridized C-H Bonds Trifluoromethylation
More informationAdditions to Metal-Alkene and -Alkyne Complexes
Additions to tal-alkene and -Alkyne Complexes ecal that alkenes, alkynes and other π-systems can be excellent ligands for transition metals. As a consequence of this binding, the nature of the π-system
More informationH H H OH OH H OH H O 1 CH 2 OH
Name 215 F07-Exam No. 3 Page 2 I. (29 points) Streptomycetes are soil-dwelling, filamentous, Gram-positive saprophytic bacteria. They are responsible for over 50% of the known microbial metabolites, including
More informationCatalyzed N-acylation of carbamates and oxazolidinones by Heteropolyacids (HPAs)
Catalyzed -acylation of carbamates and oxazolidinones by eteropolyacids (PAs) Ali Gharib 1,2 *, Manouchehr Jahangir 1, Mina Roshani 1 1 Department of Chemistry, Islamic Azad University, Mashhad, IRA 2
More informationDiels Alder Cycloaddition Strategy for Kinetic Resolution of Chiral Pyrazolidinones
Iowa State University From the SelectedWorks of Levi M. Stanley August, 2009 Diels Alder Cycloaddition Strategy for Kinetic Resolution of Chiral Pyrazolidinones Mukund P. Sibi Keisuke Kawashima Levi M.
More informationCHM 320 Laboratory Projects Spring, 2009
M 320 Laboratory Projects Spring, 2009 I. Enantioselective Reduction of Benzofuran-2-yl Methyl Ketone using Enzymes from arrots. Typically, the reduction of an unsymmetrical, achiral ketone with a hydride
More informationMechanistic Studies of Proline-Catalyzed Reactions
chanistic Studies of Proline-Catalyzed Reactions N C 2 Jack Liu July 25, 2006 ow It Got Started (L)-proline (47 mol %), 1 N Cl 4, CN, reflux, 22 h 87%, e.r. = 84/16 Eder, U.; Sauer, G.; Wiechert, R. German
More informationDenmark Group Meeting. & Electrophilic rearrangement of amides
Denmark Group Meeting Palladium catalyzed Dearomatizationeaction & Electrophilic rearrangement of amides 11 th Bo Peng th Feb. 2014 1 https://maps.google.com 2 Palladium catalyzed Dearomatization eaction
More informationZr-Catalyzed Carbometallation
-Catalyzed Carbometallation C C C C ML n C C ML n ML n C C C C ML n ML n C C ML n Wipf Group esearch Topic Seminar Juan Arredondo November 13, 2004 Juan Arredondo @ Wipf Group 1 11/14/2004 Carbometallation
More informationStereoselective reactions of enolates: auxiliaries
1 Stereoselective reactions of enolates: auxiliaries Chiral auxiliaries are frequently used to allow diastereoselective enolate reactions Possibly the most extensively studied are the Evan s oxazolidinones
More information