39200-48-1Relevant articles and documents
Memory of chirality trapping of low inversion barrier 1,4-benzodiazepin-2- one enolates
Carlier, Paul R.,Lam, Polo C.-H.,DeGuzman, Joseph C.,Zhao, Hongwu
, p. 2998 - 3002 (2007/10/03)
We have previously demonstrated that chiral, enantiopure 3-substituted 1,4-benzodiazepin-2-ones undergo retentive deprotonation/trapping at -78°C, if the N1-substituent is sufficiently large (e.g., i-Pr). Stereocontrol in this reaction is attributed to the formation of an enantiopure, conformationally chiral enolate; at -78°C a large N1 substituent (e.g., i-Pr) is needed to impart a sufficient barrier to enolate racemization. Herein, we report strategies to achieve high enantiomeric excess in deprotonation/alkylation of low inversion barrier 1,4-benzodiazepin-2-ones featuring small N1 substituents.