Platinum carbon bond formation via Cu(i) catalyzed Stille-type transmetallation: reaction scope and spectroscopic study of platinum-arylene complexes

The preparation of Pt(ii) complexes of the type trans-L2Pt(Ar)Cl, L2Pt(Ar)2, and L2Pt(Ar)(Ar') (L = PBu3, Ar = arylene) by CuI catalyzed reaction of cis-(PBu3)2PtCl2 with aryl-stannanes is reported. The reactions proceed at 25-60 °C in moderate to good yields. The reaction is demonstrated to occur with phenyl- and 2-thienyl-stannanes that include a variety of functionality, and all of the resulting Pt-aryl complexes were fully characterized by (1)H, (13)C, and (31)PNMR spectroscopy, as well as mass spectroscopy. Photophysical properties of the L2Pt(Ar)2, and L2Pt(Ar)(Ar') complexes were measured, including steady-state absorption, photoluminescence, and photoluminescence quantum yields, in order to understand how attachment of the platinum metal influences the excited state properties of the arylene ligands. This work affirms that CuI catalyzed coupling between Ar-SnR3 and L2PtCl2 is a useful platinum-carbon bond formation reaction.