ESR studies on reactions of dicyclopentadienyl dicarbonyl titanium with organic halides

Abstract

AbstractESR method was used to elucidate the mechanism of the reactions of alkyl, allyl or benzyl halides with dicyclopentadienyldicarbonyl titanium. The paramagnetic [intermediates of the reactions were identified during the course of the reactions. The reaction mechanism based on ESR findings and the products analyses is postulated to operate on radical pathways. When alkyl halides were used to react with the organometallic compound 1, the intermediate found was [Cp2Ti(CO)X] (C), and the main product was identified to be dicyclopentadienyl‐acyl‐halo titanium (3), an insertion of TiCO into R‐X, i.e. [Cp2Ti‐C(0)R] X. When allyl or benzyl halides were used, the intermediate found was [Cp2TiX] (B), and the main products were identified to be the dicyclopentadienyl titanium dihalides and the coupling products of allyl or benzyl groups.