ABSTRACT
Steric factors lead to deviations from the normal tetrahedral coordination around the Mg atom. The crystal structure of bis(trimethylsilyl)methylmagnesium chloride monodiethyl etherate [Compound 1] indicates that the compound has a trigonal planar geometry [4] . The unusual coordination results from the steric bulk of the trimethylsilyl group which prevents the coordination of a second ether solvent.
