Exploring Two Reactions of Ketones with Ge[CH(SiMe₃) ₂]₂: CH and OH Insertion

Herein we report the CH insertion of a stable germylene, Ge[CH(SiMe ₃)₂]₂, into the α-CH bonds of the acetyl-containing ketones acetone, butanone, and cyclopropyl methyl ketone. This CH insertion reaction requires the presence of MgCl₂, yet the reaction can be successfully carried out in hydrocarbon, aromatic, and ethereal solvents. In the absence of MgCl₂, these acetyl-containing ketones do not undergo CH insertion but instead undergo an OH insertion to give a germyl vinyl ether. A number of other ketones, including the acetyl-containing pinacolone, have been observed to only undergo insertion into the OH bond even in the presence of MgCl₂.