Group 11 complexes with the bidentate (SePPh2)2CH2 and tridentate [(SePPh2)2CH]– ligands

The reaction of (SePPh2)2CH2 with group 11 metal complexes such as [Au(C6F5)3(tht)] (tht = tetrahydrothiophene) affords the complex [Au(C6F5)3(SePPh2CH2PPh2Se)] in which the ligand coordinates to the gold(III) center only through one selenium atom. The treatment of the ligand with Ag(OTf) or [Cu(NCMe)4]PF6 leads, depending on the molar ratio, to the complexes [Ag2{(SePPh2)2CH2}2](OTf)2 or [M{(SePPh2)2CH2}2]X (M = Ag, X = OTf; M = Cu, X = PF6; OTf = CF3SO3) in which the phosphine selenide ligand coordinates as a bidentate bridging or chelating ligand through the Se,Se atoms. The reaction of (SePPh2)2CH2 with [Au(C6F5)2(acac)] (acac = acetylacetonate) occurs with deprotonation of the methylene group, and the methanide complex, [Au(C6F5)2(SePPh2CHPPh2Se)], is obtained, with a bidentate chelate Se,C coordination to the gold(III) center. The selenium atom can react further with other metal complexes such as [Au(C6F5)3(tht)] to give the dinuclear species [Au(C6F5)2{SePPh2CHPPh2SeAu(C6F5)3}], in which the ligand coordinates in a tridentate Se,C,Se form. The crystal structure of [Au(C6F5)2{SePPh2CHPPh2SeAu(C6F5)3}] has been established by X-ray diffraction.