Application of the Evans aziridination procedure to 2-substituted acrylates and cinnamates: An expedient route to α-substituted α- and β-amino acids
摘要:
Reaction of the title compounds with Phl=NSO2Ar (Ar = p-tolyl or p-nitrophenyl) in the presence of catalytic copper (II) triflate in acetonitrile gave the corresponding 2 and/or 3-substituted aziridine-2-carboxylates in generally; good yields. The latter, on reaction with nucleophiles, gave alpha-substituted alpha- or beta-amino acids depending on the pattern of substitution on the aziridine ring. (C) 1998 Elsevier Science Ltd. All rights reserved.
The Addition Reaction of Samarium Enolates and 2-Haloenolates Derived from Esters, and Amides to Imines. Totally Stereoselective Synthesis of Enantiopure 3,4-Diamino Esters or Amides
addition reaction of samarium enolates and 2-haloenolates derived from esters and amides to imines takes place in an efficient manner. A novel protocol to perform the addition reaction of samarium enolates derived from esters or amides to chiral 2-aminoimines, with total stereoselectivity and without racemization, is also reported. The use of samarium enolates in place of other classic metallic enolates
The Use of Samarium Enolates, A Novel Alternative in the Addition Reactions to Imines. Synthesis of 3-Amino Esters, Amides and Enantiopure 3,4-Diamino Esters
作者:José M. Concellón、Humberto Rodríguez-Solla、Carmen Simal
DOI:10.1002/adsc.200900189
日期:2009.6
Abstractmagnified imageAn efficient reaction of tosylimines with a range of samarium enolates (derived from esters, and amides) is reported. The reaction with the α‐dibenzylamino‐N‐tert‐butanesulfinimine derived from chiral phenylalaninal afforded the corresponding enantiopure 3,4‐diamino ester with very high diastereoselectivity.