Phase Transfer Catalyst (PTC) Catalyzed Alkylations of Glycinamides for Asymmetric Syntheses of ¥á-Amino Acid Derivatives

Bulletin of the Korean chemical society

Dongyeol Lim¹  Yong Sun Park¹  Hyun Ju Kim¹ 

关键词: Phase transfer catalyst;    Amino acids;    Chiral auxiliary;    Crown ether;    Alkylation.;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

The chiral amine auxiliary mediated stereoselective alkylation reactions of glycinamides 1-6 and 15-17 using phase transfer catalyst (PTC) for liquid-solid extraction are described. The secondary N-(diphenylmethylene) glycinamides 1, 2 and 3 give better selectivities and yields than tertiary N-(diphenylmethylene) glycinamides 4, 5 and 6. Alkylation of the glycinamide 1 and 2 using 18-Crown-6 as a PTC in toluene at -40�? gives best selectivities and yields. Alkylations of N-(4-chlorophenylmethylene)glycinamides 15, 16 and 17 under same PTC conditions give �?, �?-disubstituted amino acid derivatives 18, 19 and 20 with low diastereoselectivities.

【 授权许可】

Unknown