Syntheses and Crystal Structures of Nickel and Manganese Complexes Containing N-Propionylpicoloylhydrazide

The two title complexes containing L- (HL = N-propionylpicoloylhydrazide) have been synthesized. They are [NiL2] (1, C18H20N6NiO4, Mr = 443.11) and [MnL2] (2, C18H20N6MnO4, Mr = 439.34). They both belong to monoclinic system, space group P21/c, with a = 12.745(1), b = 8.5690(8), c = 18.259(2) ? b = 100.950(3), V = 1957.8(4) ?, Z = 4, Dc = 1.503 g/cm3, F(000) = 920, m(MoKa) = 1.029 mm-1, R = 0.0410, wR = 0.1069 (for 3029 observed reflections with I≥2s(I)) and S = 1.029 for 1; and a = 12.553(2), b = 8.360(1), c = 19.074(3) ? b = 101.329(6), V = 1962.7(5) ?, Z = 4, Dc = 1.478 g/cm3, F(000) = 908, m(MoKa) = 0.711 mm-1, R = 0.0637, wR = 0.1648 (for 2587 observed reflections with I≥2s(I)) and S = 1.034 for 2. In these complexes, the nickel or manganese reveals an aberrant octahedral coordination geometry with a N4O2. In the crystal there exist several intermolecular hydrogen bonds through which one-dimensional structures were formed. n(C = O) and n(CN) are shifted to lower frequencies in IR spectra; p-p* and d-p* charge-transitions are observed in their electronic spectra.