Thermolysis of [TiMe2(eta(5)-C5Me4Ph)(2)] (4) at 145 degrees C for 5 h afforded the singly tucked-in paramagnetictitanocene [Ti(III)(eta(5)-C5Me4Ph){eta(5):eta(1)-C5Me3Ph(CH2)}] (9). In distinction to the singly tucked-in permethyltitanocene [Ti(III)(eta(5)-C5Me5)(eta(5):eta(1)-C5Me4(CH2))] (1) which was found crystallographically disordered [J.M.
Fischer, W.E. Piers, V.G.
Young, Jr., Organometallics 15 (1996) 2410] the single crystal X-ray diffraction analysis of 9 afforded molecular parameters with nearly by one order better precision as measured by esd-values.