Transmetalation occurs upon addition of HgCl2 to (8-quinolyl)SnMe3 to yield (8-quinolyl)HgCl. The molecule features a frustrated Hg-N Lewis pair; however the mercury(II) center showed low affinity for sulfur Lewis bases, S8 or thiophene. In the presence of NH4SCN, ligand redistribution led to R2Hg. The molecule was found as linear or bent polymorphs, depending on the solvent of recrystallization. The geometry about Hg(II) in the bent polymorph is distorted trigonal prismatic that features a C-Hg-C angle of 84°, weak intramolecular Hg-N contacts, and two intermolecular η(2)-quinoline contacts in which the neighboring R2Hg molecule participates as a bis-η(2)-bidentate ligand.