A novel stereoselective synthesis of substituted γ-butyrolactones
作者:Juan C. Carretero、Javier Rojo
DOI:10.1016/s0040-4039(00)60201-0
日期:1992.11
A newstereoselectivesyntheticroute for the preparation of cis and trans disubstituted (and trisubstituted) γ-lactones starting from the readily available α-phenylsulfonyl-α,β-unsaturated esters 3 or α-phenylsulfonylbutenolides 4 is described. This method is based on the conjugate addition of Me3Al to compounds 3 and 4, which occurs with high, though opposite, facial selectivity.
Stereoselective synthesis of substituted γ-butyrolactones from γ-hydroxy-α,β-unsaturated phenyl sulfones
作者:Javier Rojo、Mercedes García、Juan C Carretero
DOI:10.1016/s0040-4020(01)80181-2
日期:1993.1
α-(phenylsulfonyl)-α,β-unsaturated esters 3 or α-(phenylsulfonyl)butenolides 4 is described. This method is based on the conjugateaddition of organoaluminum reagents (Me3Al, Et3Al and Et2AlCN) to substrates 3 and 4. Whereas the conjugateaddition to Michael acceptors 3 occurs with complete syn-selectivity, the conjugateaddition to butenolides 4 is usually anti-selective. This methodology has been applied