Syntheses, structural characterizations and electronic absorption spectra simulation of three phenylimido substituted hexamolybdates incorporating a remote chloro group

Three monofunctionalized organoimido derivatives of [Mo6O19]2− bearing an electron-withdrawing chloro group (R = p-ClC6H41, m-ClC6H42, or o-ClC6H43) have been prepared in high purity and moderate to good yields using an easy reaction route of [α-Mo8O26]4− with corresponding aromatic amine hydrochlorides or a mixture of aromatic amines and their hydrochloride salts in the presence of N,N′-dicyclohexylcarbodiimide (DCC). These complexes have been characterized by 1H NMR, IR, UV–Vis, UV–Vis-NIR reflectance spectroscopy, cyclic voltammetry, and their semiconductive and redox properties were explored by these techniques. Their electronic absorption spectra were also interpreted based on first-principles electronic structure calculations and these features of the simulated spectra are qualitatively consistent with the observed UV spectra. Additionally, the composition and structure of compounds 1 and 2 were further confirmed by X-ray single-crystal diffraction studies.

Graphical abstractThree chloro-functionalized organoimido substituted hexamolybdates, (Bu4N)2[Mo6O18(NR)], (R = p-ClC6H41, m-ClC6H42, or o-ClC6H43) were prepared in high purity and moderate to good yields using a convenient route of the reaction of [α-Mo8O26]4− with corresponding aromatic amine hydrochlorides or a mixture of aromatic amines and their hydrochloride salts in the presence of N,N′-dicyclohexylcarbodiimide with easy bench operation. Besides common structural characterization, their electronic absorption spectra were further interpreted based on first-principles electronic structure calculations.Figure optionsDownload full-size imageDownload as PowerPoint slide