Anion directed structural diversity in zinc complexes with conformationally flexible quinazoline ligand: structural,
Nidhi Dwivedi1, Sumit Kumar Panja, Monika
1Department of Chemistry, Mahila Maha Vidyalaya, Banaras Hindu University, Varanasi 221005, India. sunkari.s7@gmail.com.
Abstract:
In this paper, we report the synthesis, structure and photophysical studies of four new complexes of conformationally flexible 6-chloro-4-phenyl-2-(pyridin-2-yl)quinazoline ligand (L) with Zn(ii). The coordinating ability of the ligand and geometrical preferences of the resultant complexes are tuned by varying the anion of the metal salt as confirmed by structural and DFT studies. The choice of the metal salt (especially anion) directs the stabilisation of different conformations of the ligand arising out of twisting of the pyridyl ring with respect to the quinazoline ring, resulting in complexes with different nuclearity (monomer/dimer) as well as different coordination geometries (tetrahedral/trigonal bipyramidal/octahedral). Photophysical properties are also found to be tuned due to conformational changes on complexation. DFT studies on the ligand establish the conformationally stable forms as observed in the reported structures.
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