Dalton communications. Exchange of organoimido groups at a mononuclear titanium centre and a crystallographic evaluation of the relative structural influences of the NBu^t, NC6H4Me-4 and NC

The tert-butylimido complex [Ti(NBut)Cl2(py)3] 1a (py = pyridine) undergoes exchange reactions of the NBut ligand with arylamines RNH2 to form the arylimido derivatives [Ti(NR)Cl2(py)3] (R = C6H4Me-4 1b, C6H4NO2-4 1c or C6H3Me2-2,6 1d); comparison of the crystal structures of 1a-1c gave a direct evaluation of N-substituent effects in d0, six-co-ordinated organoimido complexes.