[EN] PREPARATION OF ß-PHENYL-ISOSERINE DERIVATIVES<br/>[FR] PRÉPARATION DE DÉRIVÉS DE ?-PHÉNYL-ISOSÉRINE
申请人:ORGANOCLICK AKTIEBOLAG
公开号:WO2010024762A1
公开(公告)日:2010-03-04
A process for stereoselective synthesis of a β-phenylisoserine comprises reacting a carbonyl imine R-C=N-CO-OR1 with a protected α- oxyaldehyde X1O-CH2CHO in the presence of a chiral amine catalyst and oxidizing aldehyde so obtained.
Zn-ProPhenol Catalyzed Enantio- and Diastereoselective Direct Vinylogous Mannich Reactions between α,β- and β,γ-Butenolides and Aldimines
作者:Barry M. Trost、Elumalai Gnanamani、Jacob S. Tracy、Christopher A. Kalnmals
DOI:10.1021/jacs.7b11361
日期:2017.12.20
We report a Zn-ProPhenol catalyzedreaction between butenolides and imines to obtain tetrasubstituted vinylogous Mannich products in good yield and diastereoselectivity with excellent enantioselectivity (97 to >99.5% ee). Notably, both α,β- and β,γ-butenolides can be utilized as nucleophiles in this transformation. The imine partner bears the synthetically versatile N-Cbz group, avoiding the use of
Enantio- and Diastereoselective Mannich Reactions of ß-Dicarbonyls by Second Stage Diastereoconvergent Crystallization
作者:William R. Cassels、Evan T. Crawford、Jeffrey S. Johnson
DOI:10.1021/acscatal.3c01515
日期:2023.5.19
The synthesis of chiral α-monosubstituted-ß-dicarbonyls is a challenging task in asymmetric catalysis due to the rapid, typically uncontrolled, product racemization or epimerization under most reaction conditions. For this reason, diastereoselective additions of unsubstituted ß-dicarbonyls to π-electrophiles are unusual. Herein, we disclose a simple catalytic crystallization-driven enantio- and diastereoselective