The Ring Opening of Unsymmetrical Allylic, Benzylic, Propargylic, and Si‐Substituted Epoxides by Titanium Acetylides: A Convenient Access to Certain 2‐Substituted 3‐Butyn‐1‐ols

Epoxides bearing aryl, alkenyl, alkynyl, and trimethylsilyl substituents react with titanium acetylides at the higher substituted carbon atom exclusively; the 2‐substituted 3‐butyn‐1‐ols thus formed are isolated in 33–79% yield. The dependence of the yield on the solvent, the ratio of the reactands, and their structure is discussed and a reaction mechanism is proposed.