Novel p-tolylimido rhenium(V) complexes incorporating quinoline-2-carboxylate ion – Synthesis, X-ray studies, spectroscopic characterization and DFT calculations

Novel p-tolylimido rhenium(V) complexes trans-[Re(p-NC6H4CH3)X2(quin-2-COO)(PPh3)] and cis-[Re(p-NC6H4CH3)X2(quin-2-COO)(PPh3)]·MeCN have been obtained in the reactions of [Re(p-NC6H4CH3)X3(PPh3)2] (X = Cl, Br) with quinoline-2-carboxylic acid. The compounds were identified by elemental analysis IR, UV–Vis spectroscopy and X-ray crystallography. The electronic structures of trans- and cis-halide isomers of [Re(p-NC6H4CH3)Cl2(quin-2-COO)(PPh3)] have been calculated with the density functional theory (DFT) method. Additional information about binding in the compounds [Re(p-NC6H4CH3)Cl2(quin-2-COO)(PPh3)] with cis- and trans-halide arrangement has been obtained by NBO analysis. The electronic spectra of trans and cis isomers of [Re(p-NC6H4CH3)Cl2(quin-2-COO)(PPh3)] were investigated at the TDDFT level employing B3LYP functional in combination with LANL2DZ.

Graphical abstractNovel p-tolylimido rhenium(V) complexes have been obtained and identified by elemental analysis IR, UV–Vis spectroscopy and X-ray crystallography. The electronic structures of trans- and cis-halide isomers of [Re(p-NC6H4CH3)Cl2(quin-2-COO)(PPh3)] have been calculated with the density functional theory (DFT) method. Additional information about binding in the compounds [Re(p-NC6H4CH3)Cl2(quin-2-COO)(PPh3)] has been obtained by NBO analysis.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Reactivity of [Re(p-NC6H4CH3)Cl3(PPh3)2] towards quinoline-2-carboxylic acid was examined. ► Novel p-tolylimido rhenium(V) complexes were synthesised and characterized. ► The spectroscopic features of the imido compounds were investigated by DFT and TD-DFT.