Titanium imido complexes with tetradentate Schiff base ligands

New mono- and binuclear titanium imido complexes supported by tetradentate, dianionic N2O2-donor Schiff base ligands were prepared in good yield from the readily available [Ti(NBut)Cl-2(py)(3)] (1a). Thus treatment of 1a with Na-2[substituted-salen] gave monomeric [Ti(NBut)(substituted-salen)] where substituted-salen = Et(2)salen (2) or Bu(4)(t)salen (4). In contrast, the binuclear complex [Ti(NBut){mu-(MeO)(2)salen}](2) (5) was obtained from 1a and Na-2[(MeO)(2)salen]. The less sterically crowded compounds 2 and 5 undergo tert-butyl imide/arylamine exchange reactions to form [Ti(N-2,6-C6H3Me2)(Et(2)salen)] (3) and [Ti(N-2,6-C6H3Me2){mu-(MeO)(2)salen}](2) (6), respectively, whereas 4 does not exhibit this kind of reactivity. The compound 3 can also be obtained directly from Na-2[Et(2)salen] and [Ti(N-2,6-C6H3Me2)Cl-2(py)(3)] (1b) Crystal data for 3: triclinic, <P(1)over bar>, a = 12.216(4) Angstrom, b = 12.312(11) Angstrom, c = 17.246(2) Angstrom, alpha = 90.352(12)degrees, beta = 102.59(2)degrees, gamma = 104.96(2)degrees, V = 2440.3(8) Angstrom(3), Z = 4, R = 0.051, R-w = 0.066 for 7011 data with I > 2 sigma(I). Crystal data for 5 . CH2Cl2: orthorhombic, Pbca, a = 14.747(4) Angstrom, b = 17.042(4) Angstrom, c = 20.545(3) Angstrom, V = 5163.5(13) Angstrom(3), Z = 4, R-1 = 0.096, wR(2) = 0.086 for 3765 data with I > 2 sigma(I). Crystal data for 6: monoclinic, C2/c, a = 17.902(5) Angstrom, b = 12.411(4) Angstrom, c = 21.068(5) Angstrom, beta = 90.27(2)degrees, V = 4681(2) Angstrom(3), Z = 4, R = 0.034, R-w = 0.039 for 3633 data with I > 2 sigma(I).