Mechanistic Studies on Programmed C―O/C―H Activation with <scp>Valence‐Adjusted Ti‐Complexes</scp>

Comprehensive Summary Two‐electron reduction of [N 2 NBn]Ti IV Cl ( 3 ) gave a highly reactive N]Ti II species, which underwent C—O bond activation THF (tetrahydrofuran) to generate [O(CH 4 ] through oxidative addition. The resulted Ti –C sp in oxametallacyclohexane was tantamount the elaborately‐designed Ti‐alkyl complexes, competent activate intramolecular C –H bond, forming ortho ‐cyclometalated complex NCH 6 H ]Ti (O n Bu) 5 ). Key intermediates were isolated and fully characterized by X‐ray crystallography. Mechanistic studies revealed that addition took place at ‐center via radical intermediate, while proceeded σ‐bond metathesis with kitelike four‐centered ‐transition state.