The steric effects on the reaction of 6,6-dialkylfulvene with organolithium have been studied. Reaction of EtLi with 6,6-dialkylfulvone readily results in the formation of reduction product. The addition products were formed by the reaction of BuLi with 6,6-dialkylfulvene. The analogous reaction of 6,6-polymethylenefulvene with organolithium was also examined Reaction of tetramethylenefulvene with aryllithium only leads to a-hydrogen elimination and in the case of penta and hexamethylenefulvene addition reaction takes place. A series of sec- and tert-alkyl and cycloalkenyl substituted titanocene and zirconocene derivatives have been prepared

Key words: CYCLOPENTADIENE P, PROTON MAGNETIC RESONANCE SPECTROMETRY, BARIUM COMPOUND, ALKENE P, TITANIUM COMPOUNDS, ZIRCONIUM COMPOUNDS