Efficient Remote Axial-to-Central Chirality Transfer in Enantioselective SmI<sub>2</sub>-Mediated Reductive Coupling of Aldehydes with Crotonates of Atropisomeric 1-Naphthamides
作者:Yan Zhang、Yongqiang Wang、Wei-Min Dai
DOI:10.1021/jo0526486
日期:2006.3.1
different 2-substituted 8-methoxy-1-naphthamides. The enantiomers of atropisomeric 8-methoxy-1-naphthamides were prepared through a chemical resolution process, and their absolutestereochemistry was determined by X-ray crystal structural analysis. It was found that the linkage between crotonate and the C2 position of 8-methoxy-1-naphthamides remarkably influenced the efficiency of remote chirality transfer
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
On the use of E-1-methoxymethoxybut-2-enyl(tri-n-butyl)stannane as a threo-selective, homo-enolate equivalent
作者:Andrew J. Pratt、Eric J. Thomas
DOI:10.1039/c39820001115
日期:——
(E)-1-Methoxymethoxybut-2-enyl(tri-n-butyl)stannane, readily available by addition of tri-n-butylstannyllithium to crotonaldehyde, and protection of the alcohol so formed using chloromethyl methyl ether, reacts on heating with aromatic and aliphatic aldehydes to give threo-4,5-disubstituted butyrolactones.
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.