The synthesis, characterization, and reactivity of group 4 organometallics supported by 尾 鈥恉iketonates is reported. Sterically hindered 尾 鈥恉iketonates, such as 2,6鈥恉imesitylbenzoyl pinacolone ( L 1 ) and 2,6鈥恉imesitylbenzoyl acetylmesitylene ( L 2 ), preclude the formation of tetrakis鈥 and tris鈥恈helates, halting at cis 鈥恛ctahedrally coordinated M( L n )...