The utility of vinyl ethers and vinyl esters in the Khand reaction. The value of vinyl esters as ethylene equivalents and a modified synthesis of (+)-taylorione as an example
作者:William J. Kerr、Mark McLaughlin、Peter L. Pauson、Sarah M. Robertson
DOI:10.1016/s0022-328x(01)00891-9
日期:2001.7
alkenes in the Khand cyclisation reaction has been studied. Although several vinylethers reacted to give the expected oxygenated cyclopentenone products, usually with good levels of regioselectivity, the use of vinyl esters was found to afford, as the major products, reduced cyclopentenones in which the carbon–oxygen bond had been cleaved. This unexpected reaction was developed into an alternative
Development of modified Pauson-Khand reactions with ethylene and utilisation in the total synthesis of (+)-taylorione
作者:Johannes G. Donkervoort、Alison R. Gordon、Craig Johnstone、William J. Kerr、Udo Lange
DOI:10.1016/0040-4020(96)00259-1
日期:1996.5
Two complementary Pauson-Khand annulation protocols for use with the gaseous alkene, ethylene, are described. These N-oxide promoted reactions (10 examples) are shown to proceed under both mild autoclave conditions or, more conveniently, at atmospheric pressure. The developed methodology has been utilised as the key transformation in the totalsynthesis of the sesquiterpene (+)-taylorione which has
Vinyl esters as ethylene equivalents in the Khand annulation reaction
作者:William J. Kerr、Mark McLaughlin、Peter L. Pauson、Sarah M. Robertson
DOI:10.1039/a906660h
日期:——
A preparatively convenient and mild method for modified Khand cycloadditions is described; vinyl esters are employed as the olefinic reaction partner to provide cyclopentenone products more normally obtained with ethylene.