Titanium and vanadium complexes with tetraphenylimidodiphosphinate

Treatment of [Ti(OPri)2Cl2] with K(tpip) (tpip− = [N(PPh2O)2]−) followed by chlorination with HCl afforded cis-[Ti(tpip)2Cl2]. Recrystallization of [V(O)(tpip)2] from CH2Cl2-Et2O in air afforded trinuclear [(VO)3(μ-tpip)(μ-O)]3. Treatment of [Cr(NBut)Cl3(dme)] with [Ag(tpip)]4 afforded [Cr(NBut)(tpip)2Cl]. The Ti- and V-tpip complexes can catalyze oxidation of sulfides with tert-butyl hydroperoxide and H2O2.