catena-Poly[[(N,N-dimethylcyanamide-κN)lithium]-μ3-bromido]

Abstract

The title complex, [LiBr(C3H6N2)]n, is the unexpected product of a reaction beteween (Dipp)N(Li)SiMe3(Dipp = 2,6-diisopropylphenyl), Me2NCN and CuBr. The compound is a one-dimensional polymer with a step structure derived from the association of inversion dimers, formed by bromido ligands bridging two Li+cations, each of which carries a dimethylcyanamide ligand. The planar (LiBr)2unit of the polymer core has a regular rhombic shape [Li—Br—Li 77.55 (16)° and Br—Li—Br 102.45 (16)°]. These (LiBr·NCNMe2)2dimers represent the repeat unit of a polymer system propagated by additional Br—Li and Li—Br bonds generating an infinite step structure along thea-axis direction.