Metallorganische Clusterkomplexe mit flächenüberbrückenden Aren‐Liganden, 5[1a]. C–H‐Aktivierung und Bildung eines μ3‐Aren‐Komplexes: Konkurrenzreaktionen beim Aufbau von (CpCo)3‐Clusterkomplexen mit Vinylbenzolen als Liganden

Abstract

Organometallic Clusters with Face‐Capping Arene Ligands, 5[1a].–C–H Activation and Formation of a μ3‐Arene Complex: Competing Reactions During Assembly of (CpCo)3 Cluster Complexes with Vinylbenzenes as LigandsA number of ring‐substituted styrenes R(C6H4)C2H3 (R=CH3, F) reacts with [CpCo(C2H4)2] (1) to give both the cluster complexes [(CpCo)3{μ3‐η2:η2:η2‐(C6H4R)C2H3}] [2a (R=p‐CH3), 2c (R=m‐F), 2d (R=p‐F)} with Co3 face‐capping arenes and [(μ2‐H)(μ3‐H)(CpCo)3{μ3‐1‐s̀:2‐s̀:η2‐HCC(C6H4R)}] [7a (R=p‐CH3), 7b (R=o‐F), 7c (R=m‐F), 7d (R=p‐F)] with Co3 face capping alkynes derived from dehydrogenation of the vinyl group. The X‐ray structure analysis of 7a confirms the 1‐s̀:2‐s̀:η2 coordination of the bridging alkyne ligand. In solution the complexes 7 are fluxional and exhibit migration of the alkyne and hydride ligands on the Co3 cluster.