Generation of sulfur ylides by the desilylation of α-trimethylsilylbenzyl sulfonium salts
作者:Albert Padwa、John R. Gasdaska
DOI:10.1016/s0040-4020(01)86662-x
日期:1988.1
The [2,3]-sigmatropic rearrangement of sulfur ylides derived via the desilylation of several α-trimethylsilylbenzyl sulfonium salts has been studied. The initially formed ylide was found to rapidly equilibrate with the thermodynamically more stable ylide. In the absence of trapping reagents, a Sommelet-Hauser type rearrangement occurs.
Synthesis of epoxides from aldehydes and tosylhydrazone salts catalysed by triphenylarsine: complete trans selectivity for all combinations of coupling partnersElectronic supplementary information (ESI) available: new compounds. See http://www.rsc.org/suppdata/cc/b2/b204252e/
作者:Varinder K. Aggarwal、Mamta Patel、John Studley
DOI:10.1039/b204252e
日期:2002.7.1
Triphenylarsine catalyses the formation of epoxidesfrom carbonyl compounds and tosylhydrazone salts. This convergent synthesis gives complete trans selectivity for all aldehyde and tosylhydrazone salt coupling partners.
Reduction of α-methylthio and α-phenylthio ketones 1 with L-Selectride gave syn-alcohols 2 in high stereoselectivity except when R1 was cyclohexyl group, while reduction with Zn(BH4)2 gave the isomeric anti-alcohols 3 provided R3 was methyl group.