Crystal structure of bis(triphenylphosphine) bis(N,N′-dibutylthiourea)silver(I) nitrate

A mixed-ligand silver(I) complex of triphenylphosphine and N,N′-dibutylthiourea (Dbtu), [Ag(Ph₃P)₂(Dbtu)₂]NO₃, is prepared and its structure in the solid state is determined by X-ray crystallography. X-ray structure of this complex shows that it is mononuclear with the silver atom coordinated by two PPh₃ and two dibutylthiourea ligands adopting a distorted tetrahedral geometry. The crystal structure shows the formation of 1-D chains through intermolecular hydrogen bonding interactions between N-H of Dbtu and nitrate ions. The new complex is also characterized by IR and NMR (¹H and ³¹P) spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding. A similar mixedligand complex is also prepared for tetramethylthiourea (Tmtu), but the structure of the resulting compound shows that it is a bis(phosphine) complex, [Ag(PPh₃)₂NO₃] rather than a mixed-ligand complex.     

Mono and Poly‐nuclear Silver(I) Complexes with Thiosaccharin and Triphenylphosphine. Synthesis,Spectroscopic and Structural Characterization of Thiosaccharinato‐bis(triphenylphosphine)silver(I) and Tetrakis{thiosaccharinato(triphenylphosphine)silver(I)}

The reaction of Ag₆(tsac)₆ ( 1 ) (tsac = thiosaccharinate anion) with triphenylphosphine gives rise to the already reported [Ag(tsac)(PPh₃)₃] complex ( 2 ) and to two new silver‐thiosaccharinate‐phosphine complexes, [Ag(tsac)(PPh₃)₂] ( 3 ) and [Ag₄(tsac)₄(PPh₃)₄] ( 4 ) (PPh₃= triphenylphosphine). Spectroscopic characterization was carried out using IR, UV‐Visible and NMR techniques and confirmed by single crystal X‐ray diffraction. In each complex a singular coordination mode for the thiosaccharinate ligand is observed. The most important features of the different coordination modes of the thionates are discussed. Compound 3 crystallizes in monoclinic system, space group Pn, with a = 11.2293(3) Å, b = 12.7282(3) Å, c = 13.6056(4) Å, β = 94.985(2)°, Z = 2; while crystals of compound 4 are monoclinic, space group P2₁/n, a = 15.024(3) Å, b = 14.681(3) Å, c = 21.914(4) Å, β = 95.31(3)°, Z = 2. The coordination around the silver atoms in both complexes consists of almost trigonal‐planar arrangements, AgP₂S in 3 and AgS₂P in 4 .