Diarylplatinum(II) complexes, [Pt(Ar)2(dmso)2] (Ar = C6H3Me2-3,5 (1a), C6H3(CF3)2-3,5 (1b), Ph (1c);
dmso = dimethyl sulfoxide) and [Pt{C6H3(CF3)2-3,5}2(NCCH3)2] (2b), were prepared and fully
characterized. Heating mixtures of 2-phenylpyridine (PhpyH) with the complexes in solution at 50 °C
caused coordination of PhpyH and its cyclometalation accompanied by elimination of arene to produce
monoarylplatinum(II) complexes with a solvent ligand, [Pt(Ar)(Phpy)(dmso)] (Ar = C6H3Me2-3,5 (3a),
C6H3(CF3)2-3,5 (3b), Ph (3c)) and [Pt{C6H3(CF3)2-3,5}(Phpy)(NCCH3)] (4b). The rate of the reactions
decreased in the order 1a > 1c > 2b > 1b. Crystal structures of 3a,c and 1H NMR spectra of the complexes
showed that the aryl ligand and phenyl group of the Phpy ligand occupied cis positions. A diarylplatinum
complex with a monodentate phenylpyridyl ligand, [Pt(C6H3Me2-3,5)2(CF3PhpyH)(dmso)] (5), was isolated
and characterized using X-ray crystallography. The neutral arylplatinum(II) complex 4b underwent
exchange of the acetonitrile ligand more easily than the cationic complex, [Pt{C6H3(CF3)2-3,5}(bpy)(NCCH3)]+, because of the C-bonded phenyl group of the Phpy ligand had a greater trans effect than the
N-bonded pyridyl group of bpy. Oxidative addition of I2 to 3a,b and 4b readily gave Pt(IV) dimeric
complexes with bridging iodo ligands, [(Pt(Ar)(Phpy)I)2(μ-I)2] (Ar = C6H3Me2-3,5 (7a), C6H3(CF3)2-3,5
(7b)). The dimeric structure of 7b was confirmed using X-ray crystallography.