- Two novel bridging-tridentate ligands, 4,6-di-( 4,6-dimethyl-2-pyridylthio) -2-methyl pyrimidine, 1, and 4,6-di-(4,6-dimethyl-2-pyridylamino)-2-methylpyrimidine, 2, have been synthesized and characterized. Both ligands 1 and 2 show an intriguing ability to reduce Cu(II) to Cu(I) ions. The ligand 1 reacts with Cu(O3SCF3)2 to form the Cu-1 complex which can be crystallized from the methanolic solution by adding diethylether: tridinic space group, P 1 (Number 2) with a = 8.234 (6) A, b = 11.224 (8) A, c = 11.748 (6) A, = 96.40 (2)A, = 100.43 (3)A, = 102.70 (2)A, Z=1, R = 0.0427, wR = 0.1155. The Cu-1 complex contains two Cu (1) ions and two units of the ligand 1 in which each Curl) coordinates to 3 N donors oriented into a distorted trigonal planar geometry. Similarly, the ligand 2 reacts with Cu(O3SCF3)2 to form the Cu-2 complex. Spectroscopic and elemental analysis results reveal that Cu-2 has a structure similar to Cu-1. The pi-stacking interaction of the pyrimidine rings may be aTwo novel bridging-tridentate ligands, 4,6-di-( 4,6-dimethyl-2-pyridylthio) -2-methyl pyrimidine, 1, and 4,6-di-(4,6-dimethyl-2-pyridylamino)-2-methylpyrimidine, 2, have been synthesized and characterized. Both ligands 1 and 2 show an intriguing ability to reduce Cu(II) to Cu(I) ions. The ligand 1 reacts with Cu(O3SCF3)2 to form the Cu-1 complex which can be crystallized from the methanolic solution by adding diethylether: tridinic space group, P 1 (Number 2) with a = 8.234 (6) A, b = 11.224 (8) A, c = 11.748 (6) A, = 96.40 (2)A, = 100.43 (3)A, = 102.70 (2)A, Z=1, R = 0.0427, wR = 0.1155. The Cu-1 complex contains two Cu (1) ions and two units of the ligand 1 in which each Curl) coordinates to 3 N donors oriented into a distorted trigonal planar geometry. Similarly, the ligand 2 reacts with Cu(O3SCF3)2 to form the Cu-2 complex. Spectroscopic and elemental analysis results reveal that Cu-2 has a structure similar to Cu-1. The pi-stacking interaction of the pyrimidine rings may be a significant factor to cause structural distortions in both Cu-1 and Cu-2 complexes.…