Silver(I) complexes derived from versatile multidentate chelating ligand

Three novel Ag(I) coordination polymers, [{Ag3(bpsp)2·dmf·MeCN}(ClO4)3]n (1), [Ag2(bpsp)2](NO3)2 (2) and [{Ag4(bpsp)2(NO3)2·dmf}(NO3)2]n (3), were synthesized by self-assembly of AgX (X=ClO4−, NO3−) with bpsp (bpsp=2,6-bis[(2-pyrimidinyl)methylsulfanyl]-pyridine). X-ray single-crystal diffraction analyses showed that the versatile multidentate chelating ligand bpsp ligates coordinately flexible Ag(I) into 1 in a one-dimensional(1-D) zigzag chain polymer, 2 in a helical dimer and 3 in two independent 1-D zigzag chains (chain A and B), respectively. In 1, one bpsp ligand acts in an unusual pentadentate mode with two sulfur atoms and three nitrogen atoms from a pyridine ring and different pyrimidine rings coordinating to three different Ag atoms; the other bpsp ligand acts in a tridentate mode with three nitrogen atoms from the pyridine ring and different pyrimidine rings bridging three different Ag atoms. The bpsp ligand in 2 functions in another tridentate mode with one sulfur atom and a nitrogen atom of the pyridine ring chelating with Ag(I) and with one nitrogen atom of the pyrimidine ring ligating the other Ag(I) to form a binuclear silver(I) helicate. For chain A in 3, the bpsp ligand can serve in an unusual tetradentate fashion, in which a sulfur atom and a nitrogen atom of the pyridine ring chelate with the Ag atom to form a stable five-membered ring, and two nitrogen atoms from different pyrimidine rings bridge two Ag atoms in different directions. Similar to the bpsp molecule of pentadentate fashion in 1, bpsp molecule also serves as a pentadentate ligand in the chain B of 3. Ag atoms adopt three, one, and four different coordination fashions in 1, 2, and 3, respectively.