Direct enolization chemistry of 7-azaindoline amides: A case study of bis(tetrahydrophosphole)-type ligands

[摘要] 7-Azaindoline amides are particularly useful in direct enolization chemistry due to their facilitated enolization in soft Lewis acid/Bronsted base cooperative catalysis. The Cu(I) complex of (R,R)-Ph-BPE, a bis(tetrahydrophosphole)-type chiral bisphosphine ligand, exhibits consistently high catalytic performance and stereoselectivity irrespective of the nature of the alpha-substituent of the amides. Unexpectedly, however, alkyl-substituted bis(tetrahydrophosphole)-type ligands have substantially inferior catalytic performance. Evaluation of the optimized structures of Cu(I)/amide and Cu(l)/enolate complexes provided clues to dissecting the diverted reaction outcomes. (C) 2018 Elsevier Ltd. All rights reserved.

[发布日期] 2018-06-28

[效力级别]  Proceedings Paper

[关键词] Asymmetric catalysis;Enolates;Copper;Aldol reaction;Mannich reaction