(Dimethyl sulfoxide-κO)bis(thiosemicarbazide-κ²N¹,S)zinc dipicrate dimethyl sulfoxide solvate monohydrate

Abstract

The title complex, [Zn(CH5N3S)2(C2H6OS)](C6H2N3O7)2·C2H6OS·H2O, is composed of a [Zn(thio­semi­carbazide)2(DMSO)]2+ cation (where DMSO is dimethyl sulfoxide), and two picrate anions. In the asymmetric unit, there is also a solvent mol­ecule of DMSO and a water mol­ecule of crystallization. In the cation, the ZnII atom is five-coordinated in a distorted square–pyramidal geometry. It coordinates to the O atom of a DMSO mol­ecule and to the S and one N atom of two thio­semicarbazide mol­ecules, which behave as bidentate ligands coordinating in a trans arrangement. In the crystal, a number of N—H⋯O, O—H⋯O and N—H⋯S hydrogen bonds link the mol­ecules into two-dimensional networks. These networks are further linked via weak C—H⋯O inter­actions, forming a three-dimensional arrangement. Positional disorder in one methyl group of the coordinated DMSO molecule and in the two picrate anions was observed.

Mechanism of an Elusive Solvent Effect in Organozinc Reagent Synthesis

“…The ligand coordination environment around organozinc reagents formed through these direct insertion reactions is of the utmost importance, as it dictates the downstream reactivity of the reagent (e.g., in metalation [21] and Negishi cross‐coupling reactions [6, 10] ). DMSO, for example, has been crystallographically characterized in O ‐bound Zn II complexes [22] …”

“…DMSO,f or example, has been crystallographicallyc haracterized in O-bound Zn II complexes. [22] To explore the coordination environmenti nD MSO,astoichiometric amount of DMSO was added into a[D 8 ]THF solution of 2 (Scheme 4). Monoorganozinc iodides like 2 have been previously characterized as monomeric in THF.…”