# Six-Membered Thiolate–Thione Chelate Complexes of Group 10 ElementsSyntheses, Crystal Structures, and NMR Studies

## TL;DR

Scientists synthesized and studied new metal complexes with unique sulfur-based structures and analyzed their properties using crystallography and NMR.

## Contribution

A new class of air-stable six-membered thiolate–thione complexes with group 10 metals was synthesized and structurally characterized.

## Key findings

- The complexes exhibit a slightly distorted square planar geometry with four sulfur atoms coordinating the metal center.
- Bond length changes in the complexes indicate electron delocalization within the S–C–N–C–S framework.
- 13C NMR data show a strong influence of the metal center but minimal effect from varying alkyl chain lengths.

## Abstract

Imido-C,C’-dithiodicarbonic-O,O’-dialkyl esters (alkyl: 1 = Me, 2 = Et, 3 =
i
Pr)
were synthesized by facile synthetic protocols.
They form air-stable complexes with divalent group 10 ions (Ni­[1]2, Ni­[2]2, Ni­[3]2, Pd­[1]2, Pd­[2]2, Pd­[3]2, Pt­[1]2, Pt­[2]2, and Pt­[3]2). In their crystal structures, the metal center is coordinated by
four sulfur atoms of two anionic ligands in a slightly distorted square
planar fashion. The backbones of all complexes show distortion depending
on the bulkiness of the ligand. A comparison of bond lengths in free
ligands and their respective complexes reveals CS bond length extension
and CN bond length shortening due to electron delocalization among
the S–C–N–C–S moiety. The 13C NMR spectra show a dominating influence of the metal center, while
the effect of the different alkyl chains is negligible.