Synthesis of Asymmetric<i>N</i>-Arylaziridine Derivatives Using a New Chiral Phase-Transfer Catalyst
作者:Eagambaram Murugan、Ayyanar Siva
DOI:10.1055/s-2005-869976
日期:——
Substituted N-arylaziridine derivatives were synthesized in an enantioselective manner from N-acyl-N-arylhydroxylamine and electron deficient olefins using chiral phase-transfer catalysts (CPTCs) derived from cinchona alkaloids. The structures of the CPTCs were ascertained through various spectral techniques such as FT-IR, 1H NMR, 13C NMR, and mass spectroscopy, as well as elemental analyses. The efficiency and chiral behavior of a range of CPTCs were studied with respect to both yield and ee. The chemical yields were in the range of 24-92% and ee was 29-95%. It was observed that the S-enantiomers were more predominant than the R-enantiomers with cinchonidine as catalyst; whereas the R-enantiomers were more predominant in the case of cinchonine based CPTC. We propose here a suitable mechanism for the formation of chiral aziridines as well as optimized procedures for a range of N-arylaziridine derivatives.
利用从金鸡纳生物碱中提取的手性相转移催化剂(CPTCs),以对映体选择性方式从 N-酰基-N-芳基羟胺和缺电子烯烃合成了取代的 N-芳基氮丙啶衍生物。通过各种光谱技术(如傅立叶变换红外光谱、1H NMR、13C NMR 和质谱)以及元素分析,确定了 CPTC 的结构。研究了一系列 CPTC 在产率和ee方面的效率和手性。化学收率在 24-92% 之间,ee 为 29-95%。据观察,在以辛可尼丁为催化剂的情况下,S-对映体比 R-对映体更占优势;而在以辛可尼丁为催化剂的 CPTC 情况下,R-对映体更占优势。我们在此提出了形成手性氮丙啶的合适机制以及一系列 N-芳基氮丙啶衍生物的优化程序。