Qxidative addition of thiols to a binuclear platinum complex; the crystal structure of [Pt2(µ-S)(SCH2Ph)2(µ-Ph2PCH2PPh2)2]

Abstract

Reactions of the diplatinum(0) complex [Pt₂(µ-dppm)₃](1) with H₂S and RSH, R = alkyl or aryl, have been studied. With H₂S the products were [Pt₂H₂(µ-S)(µ-dppm)₂](2) and the cation [Pt₃H(µ₃-S)(µ-dppm)₃]⁺, probably as the HS^– salt. With RSH the products using an excess of thiol were usually [Pt(SR)₂(dppm)](4; R = Me, Et, Bu^t, CH₂CO₂Et, Ph, 4-MeC₆H₄, or PhCH₂). With HSCH₂CH₂SH the chelate complex [Pt(SCH₂CH₂S)(dppm)](5) was formed. Intermediate binuclear complexes were identified as [Pt₂H (SR)(µ-dppm)₂](7) when R = Et, and [Pt₂(SR)₂(µ-dppm)₂](6) when R = Ph or 4-MeC₆H₄. With PhCH₂SH, a major product was the ‘A-frame’ complex [Pt₂(µ-S)(SCH₂Ph)₂(µ-dppm)₂](8) whose structure has been determined by X-ray diffraction.