DAVIS, FRANKLIN A.;LAL, G. SANKAR;WEI, JIA, TETRAHEDRON LETT., 29,(1988) N 34, C. 4269-4272
作者:DAVIS, FRANKLIN A.、LAL, G. SANKAR、WEI, JIA
DOI:——
日期:——
Stereo- and regioselective formation of silyl enol ethers via oxidation of vinyl anions
作者:Franklin A. Davis、G. Sankar Lal、Jia Wei
DOI:10.1016/s0040-4039(00)80471-2
日期:1988.1
Oxidation of E- and Z-vinyl lithiums with silyl peroxides 5 affords silyl enolethers 3 in good to excellent yield with retention of configuration. This methodology represents a useful new procedure for the stereo- and regioselective synthesis of ketone enolates.
Bromide assisted addition of hydrogen bromide to alkynes and allenes
作者:Hilton M. Weiss、Kim M. Touchette
DOI:10.1039/a703569a
日期:——
The addition of 0.1 M quaternary ammonium bromide to a solution of 20% trifluoroacetic acid in methylene chloride causes a large rate increase in the reaction of non-conjugated alkynes. The initial vinyl bromide product reacts further to provide a mixture of isomeric vinyl bromides and dibromides. At high salt concentrations however, the secondary reactions are prevented and only the initial vinyl