The influence of chiral auxiliaries and catalysts on the selectivity of intramolecular conjugate additions of pyrrole to N-tethered Michael acceptors

The contribution of chiral sulfoxides as versatile auxiliaries in the field of organic chemistry has shown a prevalent interest in the asymmetric synthesis of natural products during the last 45 years. In this short review, we report the recent applications of these chiral auxiliaries to the synthesis of natural and biological active products highlighted from 2010 to 2019. We hope to allow the reader to have an overview of the potential of sulfoxide chemistry in the field of enantioselective synthesis.1 Introduction2 Diastereoselective Additions to Ketones2.1 Reduction of β-Keto Sulfoxides2.2 Reduction of β-Keto Sulfoxides Followed by Bromohydrin Forma tion3 Synthesis of an α-Amino α′-Sulfinyl Ketone Followed by Diastere oselective Reduction of the β-Keto Sulfoxide4 Diastereoselective Addition of Carbanionic Chiral Sulfoxides4.1 Addition to an Aldehyde4.1.1 Aldol Reactions4.1.2 Reformatsky-Type Reactions4.2 Additions to Chiral Sulfinimines5 Diastereoselective Cyclization Reactions Directed by a Chiral Sulf oxide5.1 1,4-Radical Additions5.2 Intramolecular Conjugate Additions5.3 Nazarov Cyclizations5.4 Diels–Alder Reactions6 Atropodiastereoselective Synthesis7 Conclusion

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Copper-Catalyzed Asymmetric Conjugate Additions of Bis(pinacolato)diboron and Dimethylzinc to Acyl-N-methylimidazole Michael Acceptors: A Highly Stereoselective Unified Strategy for 1,3,5,...n (OH, Me) Motif Synthesis

Organic Letters ◽

10.1021/acs.orglett.9b00479 ◽

2019 ◽

Vol 21 (6) ◽

pp. 1872-1876 ◽

Cited By ~ 7

Author(s):

Jimmy Lauberteaux ◽

Christophe Crévisy ◽

Olivier Baslé ◽

Renata Marcia de Figueiredo ◽

Marc Mauduit ◽

...

Keyword(s):

Conjugate Additions ◽

Michael Acceptors

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In Search of New Approaches to Asymmetric Conjugate Addition: Screening Studies on the Use of [Zn(bpy*)X(R)] Reagents and α,β-Unsaturated Amide Michael Acceptors

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20071107 ◽

2007 ◽

Vol 72 (8) ◽

pp. 1107-1121 ◽

Cited By ~ 7

Author(s):

Alexander J. Blake ◽

Daniela Giunta ◽

Jonathan Shannon ◽

Maurizio Solinas ◽

Francesca Walzer ◽

...

Keyword(s):

Ligand Exchange ◽

Conjugate Addition ◽

Nmr Studies ◽

Conjugate Additions ◽

New Approaches ◽

Michael Acceptors ◽

Derivatives Of ◽

Moderate Yield ◽

C Nmr

Conjugate additions of [Zn(bpy*)Cl(Et)] (bpy* = 4,4'-di-tert-butyl-2,2'-bipyridine) to cyclohex-2-en-1-one are promoted by ZnMe2 in 88% ee but in moderate yield under CuI phosphoramidite catalysis. In the absence of ZnMe2 the [Zn(bpy*)Cl(Et)] is inactive indicating a Schlenk-type equilibrium. Other derivatives of [Zn(bpy*)Cl(R)] (R = Bu, 4-methylbenzyl), prepared in situ from [ZnCl(R)] and the bipyridine give low yields due to competing chloride abstraction. 13C NMR studies indicate facile organo-ligand exchange between [Zn(bpy*)(Et)2] and [Zn(bpy*)Cl2] complexes. In the presence of the bipyridine, [ZnBr(allyl)] disproportionates into [Zn(bpy*)Br2] and [Zn(bpy*)(allyl)2] species. In separate studies, simple (E)-MeCH=CHCONMeR (R = Me, OMe) α,β-unsaturated amides undergo asymmetric 1,4-addition of EtMgBr in 75-99% yield and 48-79% ee in the presence of the diphosphines JosiPhos or MeDuPhos and copper(I) sources.

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Chiral Amine-Mediated Asymmetric Conjugate Additions to Vinyl Sulfones

Australian Journal of Chemistry ◽

10.1071/ch09137 ◽

2009 ◽

Vol 62 (9) ◽

pp. 951 ◽

Cited By ~ 34

Author(s):

Qiang Zhu ◽

Yixin Lu

Keyword(s):

Organic Synthesis ◽

Recent Progress ◽

Conjugate Addition ◽

Chiral Molecules ◽

Conjugate Additions ◽

Chiral Amine ◽

Michael Acceptors

Chiral molecules containing sulfone groups are useful intermediates and have found wide applications in organic synthesis. In this account, recent progress in the use of vinyl sulfones as Michael acceptors in the asymmetric organocatalytic conjugate addition is summarized.

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