α,β-Unsaturated Acyl Cyanides. 6. Self-Condensation and Conjugate Addition of Allyl, Allenyl-, Propargyl-, and Alkynyltrimethylsilanes

Article abstract of DOI:10.1021/jo00358a008

The base-induced reaction of α,β-unsaturated acyl cyanides leads to lactones resulting from a self condensation reaction.Neutral nucleophiles such as trimethylsilyl derivatives react with α,β-unsaturated acyl cyanides in the presence of titanium tetrachloride. δ-Ethylenic acyl cyanides, δ-acetylenic acyl cyanides, γ-allenic acyl cyanides, and γ-acetylenic acyl cyanides (or the corresponding acids or methyl esters) are obtained from α,β-unsaturated acyl cyanides by condensation respectively with allyl-, allenyl-, propargyl- and alkynyltrimethylsilanes.