Catalytic reductive coupling of 9-bromofluorene

Abstract

The reductive homocoupling of 9-bromofluorene is catalyzed by 0.1 mol % Ru3(CO)12 in refluxing xylene, with a TON in excess of 3000. A stoichiometric reaction affords the novel cluster Ru4(μ 3-OMe)-(μ3-OH)(μ-Br)2(CO)10, which is found to be even more catalytically active. Further reaction of this cluster with bromofluorene gives another novel cluster, Ru4(μ 4-O)(μ-Br)6(CO)8, which is inactive. © 2006 American Chemical Society.