Synthesis and reactivity of cyclometallated platinum (II) compounds containing [C,N,N′] terdentate ligands: Crystal structures of [PtCl{(CH3)2N(CH2)3NCH(4-ClC 6H3)}], [PtCl{(CH3)2N(CH2)3NCH(2-ClC6H3)}] and [PtCl{(CH3)2N(CH2)3NCH(3-(CH3)C6H3)}]

The reaction of compound cis-[PtCl2(dmso)2] with ligands RCHN(CH2)3NMe2 (1a–1h) in which R is a phenyl group containing substituents such as Cl, F, Me, NO2 and MeO produced compounds [PtCl2{(CH3)2N(CH2)3NCHR}] (2), as mixtures of Z and E isomers. When treated with an equimolar amount of sodium acetate in refluxing methanol compounds 2 gave cyclometallated platinum compounds 3 containing a terdentate [C,N,N′] ligand. The obtained compounds were fully characterized including structure determinations for compounds 3a, 3b and 3e. The effects of the substituents in the regioselectivity of the cyclometallation reaction and the reactivity of 3a and 3b with mono and bidentate phosphines were also studied.