Polynuclear silver(I) complexes of triphenylphosphine and 2-aminopyrimidine: Synthesis, structural characterization and spectroscopic properties

The reactions of triphenylphosphine (PPh3) and 2-aminopyrimidine (AMP) ligand with Ag salts in the mixed solvent of methanol (MeOH) and dichloromethane (CH2Cl2) lead to the mono-, di-, and tetranuclear complexes, [Ag(PPh3)(AMP)2](BF4) (1), [Ag2(PPh3)4(AMP)2(SO4)] (2), [Ag4 (PPh3)4(AMP)2(NO3)4]∞ (3) and [Ag4(PPh3)4(AMP)2(Ac)4]∞ (Ac = CH3COO) (4) and [Ag(PPh3)2(HCOO)]·CH2Cl2 (5). Complexes 1 and 2 are of 1D infinite chain structure controlled by intermolecular hydrogen bonds of type R22(8). In complexes 3 and 4, the 1D infinite chains are formed through the bridging-chelating anions (nitrate for 3 and acetate for 4) and the N,N′-bridging ligand AMP. Five-coordinated modes of Ag(I) are observed in 3 and 4. In the synthesis reaction of complex 5, AMP only acts as catalyst rather than ligand. All the complexes are characterized by X-ray diffraction. Compounds 1–4 are also characterized by fluorescence and 1H, 31P NMR spectroscopy.

Five new complexes [Ag(PPh3)(AMP)2](BF4) (1), [Ag2(PPh3)4(AMP)2(SO4)] (2), [Ag4 (PPh3)4(AMP)2(NO3)4]∞ (3), [Ag4(PPh3)4(AMP)2(Ac)4]∞ (4) and [Ag(PPh3)2(HCOO)]·CH2Cl2 (5) have been synthesized. Compounds 1–5 are characterized by X-ray single crystal diffraction. Compounds 1–4 are characterized by luminescence and 1H, 31P NMR spectroscopy.Figure optionsDownload as PowerPoint slideHighlights
► Five new Ag–PPh3–AMP complexes were isolated and characterized.
► Owing to bridging anions and AMP, and R22(8) hydrogen bonds, 1–4 are of infinite chain structure.
► The NMR spectra show that structures of 2–4 in solution with different counter anions are similar.
► Compounds 1–4 exhibit intense luminescence at room temperature.