Stereoselective synthesis of trans-2,3-disubstituted pyrrolidines via addition to N-acyliminium ions
摘要:
An efficient and stereoselective synthesis of trans-2,3-disubstituted pyrrolidines is described. The intermolecular alkylation of racemic N-acyliminium ions generated in situ from the corresponding 3-substituted lactams proceeds stereoselectively and in high yield. (c) 2006 Elsevier Ltd. All rights reserved.
Stereoselective synthesis of trans-2,3-disubstituted pyrrolidines via addition to N-acyliminium ions
摘要:
An efficient and stereoselective synthesis of trans-2,3-disubstituted pyrrolidines is described. The intermolecular alkylation of racemic N-acyliminium ions generated in situ from the corresponding 3-substituted lactams proceeds stereoselectively and in high yield. (c) 2006 Elsevier Ltd. All rights reserved.
Effects of remote N-(tert-butoxycarbonyl) groups on heteroatom directed lithiation at benzylic positions
作者:Robin D. Clark、Jahangir
DOI:10.1016/s0040-4020(01)90188-7
日期:1993.2
Lithiation of N-BOC-2-methylphenethylamine (6) occurs exclusively at the methyl group whereas lithiation of the phenylpropyl congener (11) is less regioselective. N-BOC-phenylpropylamine (17) is efficiently lithiated at the benzylic position while N-BOC-2-methylphenylbutylamine (23) undergoes lithiation of the methyl group but with low conversion. The results are discussed from the general perspective
N -BOC -2-甲基苯乙胺(6)的锂化仅发生在甲基上,而苯丙基同类物(11)的锂化具有较低的区域选择性。N -BOC-苯基丙胺(17)在苄基位置上被有效地锂化,而N -BOC-2-甲基苯基丁胺(23)经历甲基的锂化但转化率低。从杂原子定向金属化的一般角度讨论了结果。几种硫代衍生物可以转化为杂环,例如四氢-3-苯并ze庚因-2-酮(10),六氢-3-苯并偶氮星-2-酮(16)和3-苯基吡咯烷酮(19-22)。