Bis(selone) Complexes of Palladium(II), Platinum(II) and Gold(III): Synthesis and Structural Studies

A new class of bis(selone) based metal complexes, [MnLxCly], (M = Pd, L = 3, 3'-((2-bromo-1,3-phenylene)bis(methylene))bis(1-mesityl-1,3-dihydro-2H-imidazole-2-selone (15), n = 2, x = 2, y = 4, C64H66N8Cl4Br2Se4Pd2) (17), (M = Pt, L = 15, n = 2, x = 2, y = 4, C64H66N8Cl4Br2Se4Pt2) (18) and (M = Au, L = 15, n = 1, x = 1, y = 1, C32H33N4Se2BrAuCl) (19) were synthesized by the reaction of bis-selone (15) with Pd(COD)Cl2 (yield = 31%), Pt(COD)Cl2 (yield = 34%) and [AuCl(SMe2)] (yield = 57%) respectively. The single crystal X-ray analysis reveals that 17 and 18 exist as [2+2] dinuclear self assembled 24-membered metallamacrocycles. While the spectroscopic data for the gold(III) complex (19) indicate that it exists as novel organogold(III) bromide where a facile oxidative addition occurs across the C-Br bond. NBO analysis showed the variation of NPA charge on Se atoms from negative to positive after complexation (15: -0.25, 17: 0.08 and 18: 0.09-0.13). Moreover, the NPA (Natural population analysis) charge on metal atoms is found negative; for complex 17 and 18 (Pd: -0.133(17) and on Pt: -0.23 and -0.251 (18). However, for complex 19, gold carries a positive charge (0.15).

from #ENT-AlexandrosSfakianakis via ola Kala on Inoreader http://ift.tt/2uGTyCA