New method for generation of β-oxido carbenoid via ligand exchange reaction of sulfoxides: A versatile procedure for one-carbon homologation of carbonyl compounds
one-carbon homologation of carbonylcompounds is described. The method is based on the rearrangement of β-oxido carbenoid which is generated via the ligand exchange reaction of the sulfinyl group of α-chloro β-hydroxy sulfoxide with tert-butyllithium. Addition of the carbanion of aryl 1-chloroalkyl sulfoxides to carbonylcompounds gave the adducts in good yields. The β-oxido carbenoid rearrangement of the
A novel method for generation of carbenoid from α-chloro sulfoxides: A new and versatile procedure for one-carbon homologation of carbonyl compounds to carbonyl compounds having an α-alkyl substituent
Addition of the carbanion of 1-chloroalkyl p-tolyl sulfoxides to carbonylcompound gave the adducts, which were treated with a base followed by t-butyllithium to afford one-carbon homologated carbonylcompounds having an alkyl group at the α-position, via the β-oxido carbenoids, in moderate to good yields.
A Novel Synthesis of Methylenecyclopropane Spiro-Linked with Cycloalkanes via a Cyclization of Allylic Epoxides and Its Application to a Synthesis of Fused 3-Methylfurans
作者:Tsuyoshi Satoh、Yasushi Kawase、Koji Yamakawa
DOI:10.1246/bcsj.64.1129
日期:1991.4
Ring closure of allylicepoxides derived from 1-chloroalkyl phenyl sulfoxides and cyclic ketones with lithium diisopropylamide (LDA) in 3-Exo-Tet mode gave spiro-linked methylenecyclopropanes having a hydroxyl group in good yields. Oxidation of these compounds gave ketones, which were then treated with p-toluenesulfonic acid in 1,4-dioxane or DMSO at 100°C to give fused 3-methylfurans in good overall
A novel synthesis of carbocyclic spiro-type methylenecyclopropane derivatives
作者:Tsuyoshi Satoh、Yasusht Kawase、Koji Yamakawa
DOI:10.1016/s0040-4039(00)94456-3
日期:1990.1
A novel method is described for the synthesis of carbocyclic spiro-type methylenecyclopropane derivatives via the cyclization of allyl-epoxides, which are readily available from ketones and 1-chloroalkyl phenyl sulfoxides.
The aldols are synthesized from three compoments (1-chloroalkyl phenyl sulfoxide and two kinds of carbonyl compounds and ) through α,β-epoxy sulfoxides using lithiumdimethylcuprate as an electron-transfer reagent.