Bulletin of the Korean chemical society | |
Phase Transfer Catalyst (PTC) Catalyzed Alkylations of Glycinamides for Asymmetric Syntheses of ¥á-Amino Acid Derivatives | |
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
【 预 览 】
Files | Size | Format | View |
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RO201912010238283ZK.pdf | 54KB | download |