New structural forms of alkynylplatinum(II) complexes with R2PCH2PR2 ligands

Article abstract of DOI:10.1021/om00122a009

The complexes [PtCl₂(L-L)] react with MeC≡CH and NaOR in ROH to give the monomeric, bis(acetylide) compounds [Pt(C≡CMe)₂(L-L)]. (L-L = depm and dippm, R = Et; L-L = dppm, R = Me). [Pt₂Cl₄(dmpm)₂] reacts with MeC≡CH and NaOMe in MeOH to give the dimeric acetylide complex cis,cis- [Pt₂(C≡ CMe)₄(dmpm)₂]. The complex [Pt(C≡CMe)₂(dppm)] rearranges in solution to give trans,trans-[Pt₂-(C≡CMe)₄(dppm)₂], catalysed by a trace amount of dppm, while [Pt(C≡CMe)₂(depm)] rearranges to a mixture of all three possible isomers of [Pt₂(C≡CMe)₄(depm)₂] (i.e., cis,cis, cis,trans, and trans,trans), catalyzed by PPh₃. Addition of PPh₃ to [Pt(C≡CMe)₂(dippm)] leads only to decomposition. All products are characterized by ³¹P{¹H} and ¹H NMR spectroscopy and, in some cases, by elemental analysis.