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Polynuclear Complexes of Nickel(II) with N,N’-butylenebissalicylaldimine

Although tetradentate Schiff base transition metal complexes with either N,N'-ethylenebissalicylaldimine or N,N'-propylenebissalicylaldimine have been thoroughly investigated, less attention has been given to complexes with Schiff bases containing longer aliphatic bridging chains. Two complexes of nickel(II) with N,N'-butylene-bissalicylaldimine, (methanol)bis(N,N'-butylenebissalicylaldiminato)dinickel(II)meth-anol (1/2) (1) and triethylammonium tris(nitrato)bis(N,N'-butylenebissalicylaldiminato)-trinickelate(II) (2), have been structurally characterized. Crystal data: (1) C_39H_48N_4Ni_2O_7, M_r = 802.07, Monoclinic, Space group P 2_1/n (No 14.), Z = 4, a = 13.493(1) A, b = 19.433(2) A, c = 14.812(1) A, b = 93.558(8) ^o, V = 3876.5(6) A^3, R = 0.077, wR = 0.130. (2) [(C_2H_5)_3NH][C_36H_36N_7Ni_3O_13], M_r = 1052.94, Monoclinic, Space group P 2_1/n (No 14.), Z = 4, a = 13.335(2) A, b = 25.310(3) A, c = 13.764(2) A, b = 96.177(1) ^o, V = 4618(1) A^3, R = 0.046, wR = 0.058. The assymetric unit of (1) contains a dimeric bis(N,N'-butylenebissalicyl-aldimine)dinickel(II) molecule and three methanol molecules one of which is coordinatively bonded to the octahedrally surrounded nickel atom. Remaining methanol molecules are hydrogen bonded to the chelate ligand oxygen atoms of the complex molecule. Surprisingly, other nickel atom coordination is trigonal bipyramidal. The main structural feature of (2) is the core built up of three edge sharing distorted octahedra having metal atoms coordinated either with N_2O_4 (terminal polyhedra) or O_6 donor atom set (central octahedron).

Polynuclear nickel(II) complexes; X-ray structure determination

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