Asymmetric cyclopropane synthesis via phosphine oxide mediated cascade reactions
作者:Thomas Boesen、David J. Fox、Warren Galloway、Daniel Sejer Pedersen、Charles R. Tyzack、Stuart Warren
DOI:10.1039/b413500h
日期:——
silyloxy-THF has been converted into a cyclopropane containing three stereocentres as mixture of diastereoisomers. The mechanism of the reaction has been established and the source of stereochemical leakage proposed. An alternative stereospecific cascade reaction has been discovered.
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