ortho-Mercurated derivatives of several substituted 2-phenylpyridines and of 2-phenyl-4-(methylcarboxylato)quinoline have been prepared and characterised. C,N-chelated gold(III) derivatives, [AuCl 2 (C 6 H 4 C 5 H 3 RN)] (R=H, 3-Me, 3,5-Me 2 , 4-Pr n , 4-Bu t ) are prepared more efficiently by trans-metallation reactions than by direct reaction of AuCl 4 - with the phenylpyridines. The new gold complexes were characterised spectroscopically and a variety of substitution reactions have been effected. As is usual with unsymmetrical bidentate ligands, the softer donor atom is found trans to the N-donor of the pyridine unit. Crystal-structure determinations are reported for [Au(OAc)(pmpy)(py)]ClO 4 , [Au(ppy)(dpbt)]BPh 4 , [Au(ppy)(S 2 CNMe 2 )]BPh 4 and AuCl(pqcm) 2 [Hppy=2-phenylpyridine, Hpmpy=2-phenyl-3-methylpyridine, Hpqcm=2-phenyl-4-(methylcarboxylato)quinoline].