Some complexes containing Pt-C₅-Co₃ fragments: molecular structure of trans-Pt{C≡CC≡C-μ₃-C[Co₃(μ-dppm)-(CO)₆(PPh₃)]}₂(PPh₃)₂ determined using synchrotron radiation

Abstract

Reactions of platinum(II) chloro-phosphine complexes with Co 3(μ3-CCCCCSiMe3)(μ-dppm)(CO)7 in the presence of NaOMe have given the compounds Pt{CCCC-μ 3-C[Co3(μ-dppm)(CO)7]}2(dppe) (1), trans-Pt{CCCC-μ3-C[Co3(μ-dppm)(CO) 7]}2(PEt3)2 (2) and trans-Pt{CCCC-μ3-C[Co3(μ-dppm) (CO) 6(PPh3)]}2(PPh3)2 (3), each of which contains two Co3 clusters linked by C5 chains to the Pt centre. Electrochemical studies (CVs) show the presence of both oxidation and reduction processes, the latter probably occurring on the CCo3 cores. Ready reductive elimination of {Co 3(μ-dppm)(CO)7}2(μ3:μ 3-C10) occurs from 1 upon heating. The X-ray study of 3 was carried out using synchrotron radiation (Advanced Photon Source, Argonne, IL) to confirm its structure. © 2005 Elsevier B.V. All rights reserved.