Cyclic trimeric perfluoro-o-phenylenemercury (o-C6F4Hg)(3) readily reacts with N,N-dimethylacetamide and n-butyronitrile to form the complexes {[(o-C6F4Hg)(3)](MeCONMe2)(2)} and {[o-C6F4Hg)(3)]((PrCN)-C-n)} respectively. According to X-ray diffraction data, the amide ligands are located above and below the plane of the macrocycle, each being coordinated to all Hg atoms of the macrocycle through the O atom. The nitrite ligand is bound to the macrocycle through the N atom, all Hg atoms being also involved in this bonding.