Synthesis and crystal structures of metal(I) bromide complexes containing 4-phenylthiosemicarbazide and triphenylphosphane ligands

Two new mononuclear 4-phenylthiosemicarbazide complexes [Cu(4-PTSC)(PPh3)(2)]Br (1) and [AgBr(4-PTSC)(PPh3)(2)]center dot 0.18H(2)O (2) [where PPh3 = triphenylphosphane and 4-PTSC = 4-phenylthiosemicarbazide] were synthesized and characterized by infrared spectroscopy and single crystal X-ray diffraction analysis. In the complexes, the 4-PTSC ligand acts in a monodentate fashion through the sulfur donor site to Ag(I) ion (in 2) or exhibits bidentate chelating coordination via the sulfur and the nitrogen being both bound to the Cu(I) ion (in 1). The structures exhibit distorted tetrahedral coordination around the metal ions. In the crystal of complex salt 1, the Br anions are not bonded to the metal and are linked the complex molecules via N-H center dot center dot center dot Br hydrogen bonds to form salt pair dimers (graph set motifs R-2(1)(6) and D-1(1)(2) combining to larger R-4(2)(10) and R-4(2)(14) motifs). In complex 2, where the bromide ion is bonded to the metal, intramolecular N-H center dot center dot center dot Br and N-H center dot center dot center dot N hydrogen bonds are observed (graph set motifs S-1(1)(6) and S-1(1)(5), respectively). The complex molecules of 2 are linked to form dimers via bifurcated N-H center dot center dot center dot Br hydrogen bonds involving the amine and bromide groups (graph set motif R-4(4)(14)).