Quantum Investigation into Intermolecular Interactions between Bisphenol A and 2-Vinyl/4-vinylpyridine: Theoretical Insight into Molecular Imprinting Complexes

Publication date: Available online 21 March 2017 Source:Computational and Theoretical Chemistry Author(s): Panpan Zhang, Xiuyan Ji, Hongxing Zhang, Baohui Xia Molecular imprinting complexes of bisphenol A (BPA) templates with the isomeric functional monomers 2-vinylpyridine (2-Vpy, a) and 4-vinylpyridine (4-Vpy, b) in a molar ratio of 1:1 (1a, 1b) and 1:2 (2a, 2b) were investigated by quantum chemical calculations at the B3LYP/6-311++g(d,p) level. The optimized stable geometrical structures of the complexes revealed close contact between the N site of the functional monomer and the –OH group in BPA, with N…H(O) distances of 1.85-1.86 Å. Upon forming the imprinting complex, electrons migrated from N to –OH, and the strong O–H stretching vibration at 3453 cm-1 in isolated BPA was weakened and red-shifted by ca. 400 cm-1. The electron absorption spectra of the complexes, simulated using TD-B3LYP calculations, were a direct superposition of those of BPA and vinylpyridine. The evaluated N…H(O) interaction energies of 29-36 kJ/mol in all the complexes were equivalent to those of typical hydrogen bonding interactions. Calculation of the thermodynamic properties combined with solvent media analysis implied that mildly polar solvent at normal temperatures was thermodynamically favourable for preparing molecular imprinting complexes. Graphical abstract
Source: Computational and Theoretical Chemistry - Category: Chemistry Source Type: research
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