Single, double, and triple silver centers bound by a tetradentate N,P ligand

Abstract

The novel ligand 2-(bis(diphenylphosphinomethyl))picolylamine, BPMP-2, is synthesized via a one pot Mannich condensation reaction. The multidentate nature of BPMP-2 is manifested through the incorporation of two phosphorus and two nitrogen moieties, and is reported with various Ag(I) salts. Regardless of the Ag(I) salt used (BF4−, CF3SO3−, CF3CO2−), in the reaction of one equivalent of Ag(I) with two equivalents of BPMP-2 the coordination preference of the ligand is to chelate Ag(I) through the two phosphorus atoms and form the discrete structure, [Ag(BPMP-2)2][X] (1: X=BF4−, S1: X=tfa−, and S2: X=OTf−). In the 1:1 reaction of AgBF4 with BPMP-2, a dimer ([Ag(BPMP-2)]2[BF4]2, 2) is formed. Addition of 5,5′-dimethyl-2,2′-dipyridyl (bpy) results in more complex discrete structures, [Ag3(BPMP-2)(bpy)3][BF4]3 (3) and (Agtfa)4(BPMP-2)2(bpy)2 (4). Characterization of these coordination complexes includes multi-nuclear NMR spectroscopy, elemental analysis, single-crystal X-ray diffraction, and fluorometric studies.