α-Silylsulphones have been utilised to prepare vinylsulphones via the Peterson reaction and ketones by alkylation, reduction, and sila-Pummerer rearrangement.
A novel stereoselective route to cis-olefins via addition of vinyl cuprates to αβ-unsaturated sulphones and subsequent desulphonylation
作者:Gioacchino De Chirico、Vito Fiandanese、Giuseppe Marchese、Francesco Naso、Oronzo Sciacovelli
DOI:10.1039/c39810000523
日期:——
Dialkenylcuprates, generated by addition of dialkylcuprates to acetylene, react with αβ-unsaturated sulphones to give cis-γδ-unsaturated sulphones which can be easily desulphonylated with retention of the double-bond configuration.
addition of secondary amines to α,β- or β,β-disubstituted α,β-unsaturated esters was efficiently achieved under high pressure (10-16 kbar) in protic solvents in the absence of any catalyst. The expected cumbersome β-aminesters bearing a tertiary amine directly connected to a quaternary carbon atom could be isolated in fair to good yields. By using α,β,δ,γ,-unsaturated esters (alkyl sorbate), the addition
The reaction of singletoxygen with 2-methyl-3-phenylsulfinyl-2-butene (1a) and E2-phenylsulfinyl-2-butene (1b) gives the corresponding allyl alcohols (2a and 2b) after reduction with dimethyl sulfide. α,β-Unsaturated sulfoxides with s-trans conformation failed to proceed the ene-type oxidation but afforded S-oxidation products. On the other hand, 4-methyl-1,2,4-triazoline-3,5-dione (MeTAD) reacted
Stereoselective preparation of vinyl sulfones by protodesilylation of allyl silanes
作者:Raymond L. Funk、Joy Umstead-Daggett、Kay M. Brummond
DOI:10.1016/s0040-4039(00)60467-7
日期:1993.4
Allyl sulfones can be conjugated to furnish vinyl sulfones via allyl silane intermediates. The stereoselectivity observed in the protodesilylation step provides a new method for stereoselective preparation of (E)-di-and trisubstituted vinyl sulfones.