Mechanochemically directed metathesis in group 2 chemistry: calcium amide formation without solvent.

Ball milling CaI2 and [KN(SiMe3)2] in a 1 : 1 ratio without solvent, and then extracting the ground material with toluene, yields the synthetically valuable neutral amide [Ca(N(SiMe3)2)2] in good yield, without the contamination by calciate species that complicates solution metathesis routes. The effects on yield of grinding time, milling frequency, and calcium halide identity are also examined.