Metal Coordination to a Dimetallaoctatetrayne
The reactions of the ditungstaoctatetrayne [(Tp*)(CO)2W(≡CC≡CC≡CC≡)W(CO)2(Tp*)] with several metal complexes has been investigated. Addition of [Co2(CO)8] occurs across the internal C≡C bonds, whereas [AuCl(SMe2)] initially delivers ‘AuCl’ across the W≡C carbyne bonds before undergoing further reaction to oxidise the tungsten and replace the carbonyl ligands with chloride in [(Tp*)Cl2W(≡CC≡CC≡CC≡)WCl2(Tp*)] with retention of the ditungstaoctatetrayne bridge. Reaction with [AuCl(PR3)] (R = Ph, Cy) in the presence of AgPF6 prevents this oxidation and adds [AuPR3]+ across the W≡C bonds to give dicationic derivatives. Finally, the reaction with [Pt(nbe)3] (nbe = norbornene, bicyclo[2.2.1]hept-2-ene) and 1,5-cyclooctadiene (COD) adds a ‘Pt(COD)’ unit to one or both tungsten–carbon bonds, allowing both the mono- and diplatinum complexes to be isolated.