[1192-40-1] · C6H5CuS · Phenylthiocopper(I) · (MW 172.71)
(source of nucleophilic phenyl sulfide for preparation of lithium alkyl(phenylthio)cuprates and organophosphinecopper(I) phenylthiolate complexes)
Physical Data: mp 280 °C (dec).
Solubility: sol cold THF.
Form Supplied in: yellow solid; widely available.
Preparative Methods: one method is to treat Thiophenol with Copper(I) Oxide in ethanol at reflux to give phenylthiocopper as a yellow suspension (eq 1).1-3
Alternatively, lithiation of thiophenol and quenching with Copper(I) Iodide affords a yellow solution, which is typically reacted in situ with organometallic reagents.4
Handling, Storage, and Precautions: use in a fume hood (stench).
Lithium alkyl(phenylthio)cuprates, prepared by the addition of alkyllithiums to phenylthiocopper, are highly reactive reagents which effect selective alkyl group transfers (eq 2).5 These cuprates have been employed in a singular approach to various cyclohexenone annulation products via a-acetone Gilman reagent addition to cyclohexenecarboxylate (eq 3).6 Michael additions of these copper reagents have also provided the regioselective alkylation of octahydroisoquinolines utilizing Grignard precursors (eq 4),7 and 3-spiroannulation of cyclohexenones via an organobis(cuprate) (eq 5).8 An example of a vinylcuprate addition to an alkyl iodide in the synthesis of graveolide has been reported (eq 6).9
Phenylthiocopper has been employed in displacement reactions of activated aryl bromides to give aryl phenyl sulfides (eq 7).10 Reports of similar reactions of vinyl bromide derivatives have been published.11 Organophosphinecopper(I) thiophenoxide complexes have been isolated by reaction of trialkylphosphines with PhSCu (eq 8).12 When treated with liquid Sulfur Dioxide, these complexes have formed sulfur dioxide adducts. Other applications of phenylthiocopper include thiophenolatocopper coating of Pt, Mo, and CdS,13 and formation of thiol esters upon reaction with acid chlorides.14
William J. Hoekstra
The R. W. Johnson Pharmaceutical Research Institute, Spring House, PA, USA