Syntheses and structures of highly hindered N-functionalised alkyl and amido group 12 complexes MR 2 (M=Zn, Cd, and Hg), [MRCl] 2 (M=Zn and Hg)

Abstract

The reaction of MCl 2 (M=Zn, Cd and Hg) with Li(2-(C(SiMe 3) 2)(6-Me–C 5H 3N)), [Li(MeR)], affords mononuclear metal(II) alkyls. These, in the solid state, show intramolecular M–N interactions in their four-membered chelate rings, which progressively weaken down the series, the C–M–C angles becoming more open (〈M–N〉= 2.30(2), 2.52(2), 2.913(4) Å, C–M–C=160.7(2), 168.5(2), 180(-)°). Alkylmercury chloride complexes have been prepared by the reaction of HgCl 2 with [Li(MeR)], Li(2-(C(SiMe 3) 2)(C 5H 4N)), [Li(HR)], or Li(2-(NSiMe 3)(6-Me–C 5H 3N)), [Li(mpsa)], or from the redistribution reaction of the dialkyl (or amido) mercury complex with HgCl 2. The alkylmercury chloride complexes are dimeric or polymeric in nature with near-linear 2-coordination; (Hg–Cl=2.329(5), 2.318(4), 2.272(8) Å, Cl–Hg–C(N)=175.0(4), 174.7(4), 175.6(5)°). Cd(2-(CH(SiMe 3))(6-Me-C 5H 3N)) 2(tmen), prepared from the reaction of Li(2-(CH(SiMe 3))(6-Me–C 5H 3N)) and CdCl 2 in the presence of tmen, has also been structurally authenticated as the rac isomer with the ipso protons directed towards the tmen.