Second Order Optical Nonlinearities of Copper( II ) and Palladium( II ) Complexes with N‐Salicylidene‐N′‐aroylhydrazine Tridentate Ligands

Three new N‐salicylidene‐N′‐aroylhydrazines tridentate ligands have been prepared: N‐4‐diethylaminosalicylidene‐N′‐(4‐nitrocinnamoylhydrazine (L1), N‐4‐diethylaminosalicylidene‐N′‐4‐(2,4‐dinitrophenylethylidene)benzoylhydrazine (L2), N‐4‐diethylaminosalicylidene‐N′‐4‐(6‐nitro‐2‐benzoxazolyl)benzoylhydrazine (L3). From these ligands, mononuclear acentric complexes of Copper(II) and Palladium(II), with pyridine as further ligand, have been prepared and characterized, also by single‐crystal X‐ray analysis. These complexes show high second order nonlinear optical activity (EFISH, |µβ| up to 3000·10−48 esu, incident wavelength 1.907 μm). The properties of metallorganic polymers obtained by grafting commercial poly(4‐vinylpyridine) with ML1 fragment (M = CuII or PdII) are also reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)