Intermolecular C–H activation by reactive titanocene alkylidene intermediates

Abstract

Thermal α-H abstraction from (C5H4R)2Ti(CH2CMe3)2(R = H, Me) produces reactive titanocene neopentylidene intermediates under mild conditions, that can either be trapped with PMe3 to yield the alkylidene complexes (C5H4R)2Ti(CHCMe3)PMe3, or add C–H bonds of hydrocarbon substrates R′H (R′H = benzene, p-xylene) to the TiC double bond to produce (C5H4R)2Ti(CH2CMe3)R′; an alternative reaction pathway, insertion of the alkylidene moiety into the cyclopentadienyl C–C bond, has been observed in the presence of THF.