Abstract
Synthesis of 1, 1-disubstituted derivatives of 2, 5-diphenylsilacyclopent-3-enes and 2, 5-diphenylsilacyclopentanes was investigated.
1, 1-Disubstituted derivatives of 2, 5-diphenylsilacyclopent-3-enes having dialkoxy, 1-alkoxy-1-methyl, 1-alkoxy-1-chloro, and 1-alkyl-1-chloro were prepared by one-pot reaction of(1E, 3E)-1, 4-diphenylbuta-1, 3-diene and dichlorosilanes in the presence of magnesium. 1, 1-Dialkoxy derivatives were obtained in about 80% yield, but 1-alkyl-1-chloro derivatives were obtained under 50% yield. Each silacyclopentenes was given as the mixture of trans and two cis isomers. 1, 1-Dialkoxy derivatives were obtained as a trans rich form and 1-alkyl-1-chloro derivatives were obtained as only cis isomer. Then the hydrogenation of 1, 1-disubstituted derivatives of 2, 5-diphenylsilacyclopent-3-enes by hydrogen gas in the presence of Pd-C gave the corresponding derivatives of 2, 5-diphenylsilacyclopentanes.
