C–H and N–H activation by Pt(0) in N- and O-heteroaromatic compounds

The reactions of [Pt(PEt3)4] with various azoles afforded platinum(II) hydride complexes of the type trans-[PtH(1-azolyl)(PEt3)2], where azolyl=indolyl (1), imidazolyl (2), benzimidazolyl (3), pyrazolyl (4) and indazolyl (5), by oxidative insertion of the metal centre into the N–H bonds of the respective azoles. Pyrrole was much less reactive. Complexes trans-[PtH(R)(PEt3)2], where R=2-furyl (6), 2-benzoxazolyl (7) and 2-benzothiazolyl (8) were prepared via C–H bond activation. For benzothiazole, insertion into the C–S bond did not occur. Analogous C–H activation products with 1-methylpyrrole and dibenzofuran could not be isolated.