Crystal structure and Hirshfeld surface analysis of cyclo -tetra-bromido-1κ 2 Br ,3κ 2 Br -tetra-kis-(μ 2 -2-{[(pyridin-2-yl)meth-yl]amino}-ethane-1-thiol-ato-κ 3 N , S : S )tetra-mercury(II).

The macrometallacyclic title compound, [Hg ₄ Br ₄ (C ₈ H ₁₁ N ₂ S) ₄ ] or [((Hg L ₂ )(HgBr ₂ )) ₂ ] ( 1 ) where HL = 2-{[(pyridin-2-yl)meth-yl]amino}-ethane-1-thiol, was prepared and structurally characterized. The Hg ²⁺ complex crystallizes in the P 2 ₁ / c space group. The centrosymmetric Hg ₄ S ₄ metallacycle is constructed from metal ions with alternating distorted tetra-hedral Br ₂ S ₂ and distorted seesaw N ₂ S ₂ primary coordination environments with pendant pyridyl groups. The backfolded extended chair metallacycle conformation suggests inter-actions between each of the bis-chelated mercury atoms and Br atoms lying above and below the central Hg ₂ S ₄ plane. Supra-molecular inter-actions in 1 include a fourfold aryl embrace and potential hydrogen bonds with bromine as the acceptor. Hirshfeld surface analysis indicates that H⋯H (51.7%), Br⋯H/H⋯Br (23.0%) and C⋯H/H⋯C (9.5%) inter-actions are dominant.
(© Thomas et al. 2023.)