Synthesis of 2-methylidene-1-silacyclohexanes by intramolecular hydrosilylation

The preparation of various (hex-5-ynyl)silanes was achieved following two different synthetic approaches from readily available materials such as 4-bromobutene, 6-iodohexyne and chlorosilanes. Different reaction conditions for intramolecular hydrosilylation were tested to prepare the corresponding 2-methylidene-1-silacyclohexanes. Notably, the use of Speier’s catalyst allowed the regioselective formation of the desired products in moderate yields.

Graphical abstractA variety of (hex-5-ynyl)silanes was prepared from readily available materials and converted in the corresponding 2-methylidene-1-silacyclohexanes via intramolecular hydrosilylation. Among the catalytic system tested, Speier’s catalyst was found to be the most suitable for this transformation.Figure optionsDownload full-size imageDownload as PowerPoint slide