Unusual intra- and intermolecular Ni···H-C anagostic interactions in (N-(pyrrol-2-ylmethyl)-N-(2-phenylethyl)dithiocarbamato-S,S’)- (thiocyanato-κN)(triphenylphosphine)nickel(II): synthesis, spectral properties, crystal structure, Hirshfeld surface analysis and DFT studies

Abstract

Two new Ni(II) complexes, bis(N-(pyrrol-2-ylmethyl)-N-(2-phenylethyl)dithiocarbamato-S,S′)nickel(II) (1) and (N-(pyrrol-2-ylmethyl)-N-(2-phenylethyl)dithiocarbamato-S,S′)(thiocyanato-κN)(triphenylphosphine)nickel(II) (2) were synthesized and characterized by elemental analysis, IR, UV-vis and NMR spectroscopy. IR and ¹³C{¹H} NMR spectra of both complexes suggest that the dithiocarbamate ligands interact with metal ion as bidentate ligands. Electron spectra reveal square planar geometry for both complexes. A detailed description of crystal structure, DFT calculations and Hirshfeld surface analysis of 2 is also reported. The structure determination of 2 by X-ray crystallography confirmed the presence of four coordinated Ni(II) with distorted square planar geometry. The optimized geometry, HOMO – LUMO energy gap, molecular electrostatic potential (MEP) map and global reactivity descriptors were obtained using DFT calculations. The geometric parameters calculated for 2 using the DFT method are in good agreement with those obtained from single crystal X-ray structure determination. One of the interesting structural features of 2 are the obvious intramolecular and intermolecular C-H···Ni anagostic interactions. Hirshfeld surface analysis showed the nature of intermolecular contacts. The largest contribution to the crystal packing is from H···H interactions.

Graphical Abstract

Keywords:

• Nickel(II) complex
• dithiocarbamate
• crystal structure
• anagostic interaction