Synthesis, Characterization, and Reactivity of Copper(I) and Copper(II) Complexes of N, N'-Bis (3- (2-thenylidenimino)propyl)piperazine (tipp) and N, N'-Bis (3- (2- theny lamino) propyl) piperazine (tapp). Crystal Structure of [Cu(tapp)][C1O4]2

Copper(I) and copper(II) complexes of the new ligands N,N'-bis(3-(2-thenylidenimino)propyl)piperazine (tipp) and N,N-bis(3-(2-thenylamino)propyl)piperazine (tapp) have been synthesized. Complexes of the type [Cu(ligand)][C1O4], ligand = tipp or tapp, have been prepared by the reaction of tipp or tapp with [Cu(MeCN)4] [C1O4]. Complexes of the type [Cu(ligand)]X2 (X = C1O4-, NOf, OSO2CF3-) have been prepared by the reaction of tipp or tapp with Cu(C1O4)2-6H2O, Cu(NO3)2-3H2O, or Cu(OSO2CF3)2, respectively. The complexes have been characterized by conductivity measurements and by infrared, electronic, and EPR spectroscopy. In addition the structure of [Cu(tapp)] [C1O4]2 has been determined by diffraction methods. The [Cu(ligand)] [C1O4] 2 complexes display CuN4 coordination in solution and in the solid state. The nitrate complexes are properly described as [Cu(ligand)(ONO2)j [NO3] in both solution and the solid state, with CuN4O coordination. While the CunOSO2CF3 salts show CuN4O coordination in the solid state, they display CuN4 coordination in solution. For the Cu(I) complexes the Cu(tapp)+ ion is rapidly oxidized in solution while the Cu(tipp)+ ion is more stable and probably displays CuN2S2 or CuN4S2 coordination. For both the Cu(I) and Cu(II) complexes the tipp derivatives undergo the expected hydrolysis of the mine linkages in solution. In the solid state the Cu(tapp)2+ ion of [Cu(tapp)] [C1O4]2 displays a CuN4 coordination that is severely distorted from square planar with N-Cu-N angles as small as 74.2 (2)° and deviations from the CuN4 plane as large as 0.397 (4) Å. The disposition of the thiophene S atoms about the Cu ion is suggestive of an incipient CuN4S2 coordination. The material crystallizes with 4 formula units in space group Cl172v-C2ca of the orthorhombic system in a cell of dimensions a = 11.302 (5), b = 16.239 (7), and c = 13.948 (6) Å. A crystallographic twofold axis is imposed on the cation. The structure has been refined to a final R index on F2 of 0.079, on the basis of 167 variables and 2331 observations collected at -150 °C.