Alkylation of chiral phosphonoglycine equivalents: Asymmetric synthesis of diethyl α-amino-α-alkyl-phosphonates
作者:Giulia Cabella、Giancarlo Jommi、Roberto Pagliarin、Guido Sello、Massimo Sisti
DOI:10.1016/0040-4020(94)01059-9
日期:1995.2
A model was developed to rationalize the experimental results of the alkylation of chiral phosphonoglycine equivalents yielding α-amino-α-alkyl-phosphonates. The model studies, carried out using semiempirical calculations, have emphasized the role of the chelating effects in influencing the diastereoselectivity of the alkylation step. Chelation can be optimized by tuning the functionality of the substituent
建立了模型以合理化手性膦酰基甘氨酸等效物烷基化产生α-氨基-α-烷基膦酸酯的实验结果。使用半经验计算进行的模型研究强调了螯合作用在影响烷基化步骤的非对映选择性方面的作用。可以通过调节樟脑骨架碳C-1处取代基的官能度来优化螯合作用。如建模所建议,通过使用2d,化合物5(R = CH 3,C 2 H 5)的对映体过量得到了重大改善。