Mixed Metal Acetylides: The PtII Aryl Acetylide “[PtC6H2(CH2NMe2)22,6-(C≡C)-4]” as a Connective Fragment

Using Me3SiC≡C{Pt}Cl (1; Me3SiC≡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 = (η5-C5H4)Fe(η5-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 C2 unit of 1 have been carried out and heterotrimetallic [μ-(Me3SiC≡C{Pt}Cl][Co2(CO)6] (10) could be synthesised. The successful attachment of 1 to a Ph3PAu unit leads to linear Ph3PAuC≡C{Pt}Cl (11). Treatment of 11 with FcC≡CSnMe3 produces the heterotrimetallic rigid-rod shaped complex Ph3PAuC≡C{Pt}C≡CFc (13). Cyclic voltammetric studies carried out on these Ph3PAu-capped molecules show that the attachment of an organometallic entity on either side of the C≡C{Pt} fragment leads to a facilitation of the PtII/PtIV oxidation.