Crystal Structures and Chemical Properties of Dimesitylcadmium and Dimesitylmercury

Mesityllithium was used to synthesize dimesitylcadmium and dimesitylmercury from CdCl₂ and HgCl₂, respectively. X‐ray‐crystallographic data show that the group 12 metal compounds MMes]₂ (M = Zn, Cd, Hg) are isomorphous (monoclinic, P2₁/n). The asymmetric unit of MMes]₂ (M = Zn, Cd, Hg) consists of one mesityl group bonded to the metal atom, which is related to the second substituent by an inversion center. In addition we have investigated the reaction of BBr₃ with MMes]₂ (M = Cd, Hg) for our understanding of the reactivity of donor‐free group 12 mesityl compounds. The reaction of MMes]₂ (M = Cd, Hg) with an excess of BBr₃ produces MesBBr₂. UV‐induced conversion of HgMes]₂ in benzene yielded quantitatively mesitylene and mercury whereas irradiation of a chloroform solution of HgMes]₂ for 1290 min (λ_max = 510 nm) gave mesitylene, HgMes]Cl, and HgCl₂ in a ratio of 6:4:1. Slow concentration of the reaction solution led to the deposition of X‐ray quality crystals of the addition compound of two HgMes]Cl molecules and HgCl₂ (monoclinic space group P2₁/n).