A Combined Nmr and Electron-spin-resonance Investigation of the (c-5(ch3)(5))ti(ch2c6h5)(3)/b(c6f5)(3) Catalytic-system Active In the Syndiospecific Styrene Polymerization

The reaction of(C-5(CH3)(5))Ti(CH2C6H5)(3) with B(C6F5)(3) in chlorobenzene at 25 degrees C produces a mixture of [(C-5(CH3)(5))Ti(CH2C6H5)(2)](+) [B(CH2C6H5)(C6F5)(3)](-) (1) and Ti(III) complexes which have been characterized by NMR and electron spin resonance (ESR) spectroscopy, respectively Spectroscopic data combined with polymerisation activity measurements suggest that a Ti(III) complex is the active species in the styrene syndiospecific polymerisation