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Reaction of 2,6-diacetamidopyridine (2,6-dapyH 2 ) with mercury acetate in ethanol affords the 12-membered metallamacrocycle, [Hg 2 (μ-2,6-dapy) 2 ], in high yields resulting from deprotonation of both amide groups. The crystal structure shows that two 2,6-dapy dianions bridge the dimercury centre being bound through the amide nitrogens. The mercury atoms adopt the expected linear two-coordinate geometry [N–Hg–N 169.2 (4) and 173.5 (4)°] and the two 2,6-dapy ligands are twisted by ca. 19.3° with respect to one another. The metallamacrocycles form a coordination polymer with each mercury centre being weakly coordinated to two oxygen atoms of neighboring 2,6-dapy ligands [Hg⋯O 2.970 and 3.223 A].

Treatment of [MCl2(κ2-dppf)] (M = Pd or Pt) with two equivalents of potassium heterocyclic thionate salts (KL) affords mixed ligand complexes [ML2(κ2-dppf)] [L = 5-phenyl-1,3,4-oxadiazole-2-thionate (Phozt), 4,5-diphenyl-1,2,4-triazole-3-thionate (Ph2tzt), benz-1,3-thiazoline-2-thionate (bztzt) and benz-1,3-oxazoline-2-thionate (bzoxt)]. X-ray structures of two examples, [Pt(Phozt)2(κ2-dppf)] and [Pd(bzoxt)2(κ2-dppf)], show that the ligands are coordinated in a monodentate fashion via the sulfur atom.