Abstract

Study On The Coordination Behaviour Of Bidentate Schiff Bases Towards Zinc(II) Pseudohalides: X-Ray Structure Of [Zn(pbba)2(N3)2](pbba=N-((pyridin-2-yl)benzylidene)benzylamine)

Author(s): Barindra Kumar Ghosh, Habibar Chowdhury, Jaya Banerjee, Rajarshi Ghosh, Sk Hafijur Rahaman, Hoong-Kun Fun

Two new Schiff bases, N-((pyridin-2-yl)formylidene)benzylamine (pfba) and N-((pyridin-2-yl)benzylidene)benzylamine (pbba) have been prepared. Two series of hexacoordinated zinc(II)pseudohalide complexes of type [Zn(L)2(X)2] (L: pfba; X=N3 -, (1a); X=NCS-, (1b); X=NCO-, (1c) and L: pbba; X=N3 -, (2a); X=NCS-, (2b); X=NCO-, (2c) have been developed using these two Schiff bases. Elemental, spectral and other physicochemical results characterise the complexes. Structure of [Zn(pbba)2(N3)2] (2a) is solved by X-ray diffraction measurements. (2a) crystallizes in the orthorhombic space group P21/c with a=16.6671(2) Å, b=44.4722(8) Å, c=8.9687(1) Å, α=90.00°, β=90.00°, Z=8. Structural analyses reveal that each zinc(II) in (2a), has an distorted octahedral geometry with ZnN6 chromophore coordinated through four N atoms of two bidentate pbba units and two N atoms of terminal azide in1 mutual cis orientation. The mononuclear units are engaged intermolecular C-H…N hydrogen bonding resulting 1D molecular chain. All the complexes display intraligand[1](π- π*) fluorescence and intraligand[3](π-π*) phosphorescence in glassy solutions (MeOH at 77 K).