Scope and stereochemistry of an olefin synthesis from β-hydroxysulphones
作者:Philip J. Kocienski、Basil Lythgoe、Steven Ruston
DOI:10.1039/p19780000829
日期:——
The synthesis of olefinsfrom β-acyloxy-sulphones by reduction with sodium amalgam in methanol–ethyl acetate can be applied to the preparation of a wide variety of conjugated dienes. When used for the synthesis of 1,2-disubstituted olefins in which the new double bond is either isolated or conjugated, the reaction is highly stereoselective, and leads to the trans-isomers.
Preparation and Reaction of Phenylsulfonyl-substituted Dizinciomethane
作者:Yoko Baba、Akio Toshimitsu、Seijiro Matsubara
DOI:10.1246/cl.2007.864
日期:2007.7.5
Treatment of dibromomethyl phenyl sulfone with zinc powder in the presence of a catalytic amount of lead in THF afforded phenylsulfonyl-substituted dizinciomethane. The species converts a ketone or aldehyde into an alkenyl sulfone via a Wittig-type olefination reaction with the assistance of β-TiCl3.
α-Silylsulphones have been utilised to prepare vinylsulphones via the Peterson reaction and ketones by alkylation, reduction, and sila-Pummerer rearrangement.
Deoxygenative debromination of α-bromo-β-hydroxy (acetoxy) phenyl sulfones with samarium(II) iodide led to substituted α,β-unsaturatedsulfones in good to excellent yields. The E-isomer is the major product. A possible mechanism via an α-sulfonyl radical pathway is proposed.
Lithio iodomethyl phenylsulfoxides reacted with alkyl halides and carbonyl compounds to give adducts in good to moderate yields. Solvolysis of the carbonyl adducts led to sulfones or the ring expanded product.