Asymmetric synthesis of cyclopropanes and dihydrofurans based on phosphine oxide chemistry
作者:David J. Fox、Sean Parris、Daniel Sejer Pedersen、Charles R. Tyzack、Stuart Warren
DOI:10.1039/b606874j
日期:——
The asymmetric synthesis of gamma-azido trans-cyclopropyl ketones is accomplished via a short, simple and efficient sequence. The cyclopropanation step is achieved by an intramolecular nucleophilic ring closure, with a diphenylphosphinate leaving group, to give trans-cyclopropane exclusively. beta-Keto-diphenylphosphine oxides cyclise to form optically active dihydrofurans. All possible diastereoisomers
γ-叠氮基反式环丙基酮的不对称合成是通过短,简单和有效的序列完成的。环丙烷化步骤是通过分子内亲核闭环和二苯基次膦酸酯离去基团来完成的,从而只得到反式环丙烷。β-酮基-二苯基膦氧化物环化形成光学活性的二氢呋喃。二氢呋喃的所有可能的非对映异构体可以从相同的烯烃开始选择性地制备。