Synthesis, Isolation and Structural Characterisation of Alkoxytitanium Triflate Complexes

Treatment of [Ti(O i Pr) 4 ] with trimethylsilyl triflate results in the formation of [Ti(O i Pr) 3 (OTf)] ( 2 ) in high yield. Subsequent treatment of the triflate derivative 2 with a series of facially coordinating N 3 ‐donor ligands results in the production of a series of charge‐separated metal alkoxide salts of the general formula [{L}Ti(O i Pr) 3 ][OTf] {L = tris(pyrazolyl)methane ( 3a ), 1,3,5‐triethyl‐1,3,5‐triazacyclohexane ( 3b ), 1,3,5‐tribenzyl‐1,3,5‐triazacyclohexane ( 3c ), 1,3,5‐tris( p ‐fluorobenzyl)‐1,3,5‐triazacyclohexane ( 3d ), and 1,3,5‐tris[(1 S )‐1‐phenylethyl]‐1,3,5‐triazacyclohexane ( 3e )}. The products were characterized by 1 H and 13 C NMR spectroscopy and in the case of 3a – c by single‐crystal X‐ray diffraction. Reaction of 2 with 1,3,5‐triphenyl‐1,3,5‐triazacyclohexane results in the formation of complex 4 [{L′} 2 Ti(O i Pr) 2 (OTf) 2 ], which contains two 3,4‐dihydroquinazoline ligands (L′), a result of catalytic activation of the triazacyclohexane ligands by [Ti(O i Pr) 3 (OTf)] towards electrophilic aromatic substitution.