Bis(boryl)metallocenes .1. 1,1'-bis(diisopropylboryl)cobaltocenium cation: A novel anion-binding ligand

Three situations are observed when the new cobaltocene derivative Co(C5H4BPr2i)(2) (2) is oxidized. The cobaltocenium salt [2]PF6 (3) is obtained with [FeCp(2)]PF6 as oxidant. With Cu(OH)(2) the inverse chelate [2]OH (4) with a mu-OH group bridging the two boron centers is formed. Oxidation with C2Cl6 gives a zwitterionic chloride (5) with a trigonal and a quaternized boron center; in solution 5 is fluxional.