catena-Poly[[dichloridodimethyltin(IV)]-μ-5-methylpyrazine-2-carboxylato-κ3O:O′,N-[dimethyltin(IV)]]-μ-5-methylpyrazine-2-carboxylato-κ3O, N: O′]

The title compound, [Sn2Cl2(CH3)(4)(C6H5N2O2)(2)], forms infinite one-dimensional zigzag chains that propagate in a helical fashion along the c axis via an Sn-O=C-O-Sn-O bridge which involves the carboxylate groups of two methyl-pyrazinecarboxylate ligands. These display both chelating and bridging coordination behaviour. The asymmetric unit contains two Sn atoms; one adopts a distorted trigonal bipyramidal geometry, while the other is in a distorted pentagonal-bipyramidal configuration.