diarylthiolate

A diarylthiolate is the anionic form of a diaryl thiol, an organosulfur compound in which sulfur is attached to two aryl groups and to a hydrogen in the protonated state. Upon deprotonation, the diaryl thiol yields a diarylthiolate with the formula [Ar2S]−, a sulfur-centered monoanionic ligand. In coordination chemistry and organometallic chemistry, diarylthiolates are treated as thiolate-type ligands that can bind to metal centers through sulfur and, in some cases, participate in bridging two metals.

Preparation and structure

Diarylthiolates are typically prepared by deprotonation of a diaryl thiol (Ar2SH) with a strong base such as n-butyllithium or sodium hydride, affording lithium or sodium diarylthiolates, Li[Ar2S] or Na[Ar2S]. These anions can then be converted to metal diarylthiolates by metathesis with suitable metal salts. The geometry around sulfur is influenced by the aryl substituents, and bulky aryl groups can stabilize the anion by steric protection. The S− is the primary site of reactivity, including nucleophilic attack on electrophiles and formation of metal–sulfur bonds.

Applications

Diarylthiolates serve as ligands in a range of metal complexes, where they act as soft donors and can support various oxidation states. They appear in studies of sulfur-centered coordination chemistry, cluster synthesis, and catalysis. Their reactivity and stability depend on the electronic and steric properties of the aryl groups.

See also

Thiolate, diaryl sulfide, sulfur ligands, organometallic chemistry.

Safety

As with many organosulfur compounds, diarylthiolates and their precursors can be moisture- and air-sensitive and should be handled with appropriate inert-atmosphere techniques and protective equipment.