The configurational stability of vinyl carbanions derived from monosubstituted activated ethylenes
Abstract
The configurational stability of vinyl carbanions derived from the 1 -substituted activated ethylenes, acrylonitrile and methyl acrylate, was investigated. The pure cis-isomers of the corresponding β-deuterio-olefins were treated with benzophenone in the presence of a base in several solvents (diethyl ether, tetrahydrofuran, and diethyl ether-hexane). cis–trans Mixtures of the corresponding α-[hydroxy-[(diphenyl)methyl] derivatives formed were isolated and their composition determined. The mechanism of the formation of the two isomeric products is discussed. The vinyl carbanion derived from the β-deuterioacrylonitrile was configurationally stable, while that derived from the corresponding acrylic ester was configurationally unstable.