1,2‐Disilabicyclo[1.1.1]pentan‐4‐ones from a Disilenide and Acryloyl Chlorides.

Reactions of a disilenide, a disila analogue of vinyl lithiums, with two α,β-unsaturated carboxylic acid chlorides yield the first examples of compounds with a bicyclo[1.1.1]pentane scaffold that feature one carbon and one silicon atom at bridgehead positions; the formation of 1,2-disilabicyclo[1.1.1]pentan-4-ones is explained with initial nucleophilic substitution at the carbonyl C-atom by the nucleophilic disilenide and subsequent intramolecular [2+2]-cycloaddition of the Si=Si to the C=C double bond in a highly diastereoselective fashion.