Mixed metal acetylides: The Pt-II aryl acetylide "[PtC6H2(CH2NMe2)(2-),2,6-(C equivalent to C)-4]" as a connective fragment

Using Me3SiC=C{Pt}Cl (1; MessiC-C{Pt} = [Pt(C6H2-{CH2NMe2}(2)-2,6-{C-CSiMe3 }-4](+)) a series of platinum monoacetylides of the type XC=C{Pt}C=CR [X = SiMe3: 2, R = Ph; 3, R = (eta(5)-C5H4)Fe(eta(5)-C5H5) (abbreviated as Fc); 4, R = C6H4CN-4; 5, R = C6H4(C=CSnMe3)-4; X = H: 7, R = Ph; 8, R = Fc; 9, R = C6H4CN-4] have been prepared. Studies directed towards the coordinative properties of the Ct unit of 1 have been carried out and heterotrimetallic [mu-(Me3SiC=C{Pt}Cl][Co-2(CO)(6)] (10) could be synthesised. The successful attachment of 1 to a Ph3PAu unit leads to linear Ph3PAuC=C{Pt}Cl (11). Tre atment of 11 with FcC=CSnMe3 produces the heterotrimetallic rigid-rod shape d complex Ph3PAuC=C{Pt}C=CFc (13). Cyclic voltammetric studies carried out on these Ph3PAu-capped molecules show that the attachment of an organometal lic entity on either side of the C=C(Pt} fragment leads to a facilitation o f the Pt-II/Pt-IV oxidation.