The diamagnetic halfsandwich complexes [V(η7-C7H7)(CO)3] and [V(η5-L5)(CO)4] have been used as intermediates in the conversion of hexcarbonylvanadium, V(CO)6, to the paramagnetic trovacene derivatives, [V(η5-L5)(η7-C7H7)] [L5 = cyclopentadienyl ligand, C5H4-R (R = H (1), Me (1a), tBu (1b)) and C5Me5 (1c); indenyl (2) and 2-methylindenyl (2a)]. The molecular structure of 2a has been determined: the distances between vanadium and the center Z of the (nearly parallel) ring ligands are 193.0 pm (V-Z5) and 146.2 pm (V-Z7).