Reaktionen an μ3‐verbrückenden Alkin‐Liganden auf Heterometallclustern

Abstract

Reactions of μ3‐Bridging Alkyne Ligands on Heterometallic ClustersThe metal‐exchange methods to obtain alkyne‐bridged heterometallic clusters from RuCo2(CO)9(μ3‐RCC') (2) were improved, and the new clusters RuCoMoCp(CO)8(PhCCPh) (3c), RuCoNiCp(CO)6(MeCCPh) (5b), RuMoNiCp2(CO)5‐(MeCCMe) (6a), and HFeRuMoCp(CO)8(MeCCMe) (7a) were obtained thereby. Some of the alkyne‐bridged clusters were found to react with additional alkyne. One alkyne unit was incorporated in the products RuCoNiCp(CO)6(RCC')2 (9), two alkyne units were incorporated in the products Ru‐Co2(CO)7(RCC')3 (8). In a side reaction, butyne was trimerized to hexamethylbenzene. Radical anions of the clusters FeCo2(CO)9(RCC') (1) were formed by reduction with cobaltocene. The reaction of these radical anions with alkylating reagents was accompanied by cluster fragmentation and CO insertion converting the former alkyne ligand by acylation into the new trisubstituted oxoalkenyl ligand in the products FeCo(CO)6(μ‐CRCR'‐CR″O) (11). The constitutions of the cluster types 7, 9 and 11 were confirmed by crystal‐structure determinations.