Recent developments in the coordination and organometallic chemistry of Kläui oxygen tripodal ligands

The Kläui oxygen tripodal ligands [(η5-C5H5)Co{P(O)(OR)2}3]− (LOR− where R = alkyl group), which have been recognized as oxygen analogues of cyclopentadienyl, can form stable complexes with a range of main group and transition metal ions. This review reports on the recent developments in the coordination and organometallic chemistry of the Kläui tripodal ligands. Special attention will be paid to polynuclear M-LOEt (M = Ti, Zr) oxo and hydroxo compounds that may serve as models for group 4 metal aqua ions.