Amido-bridged double cube nitrido complexes containing titanium and magnesium/calcium

Abstract

Treatment of the single cube nitrido complexes [(thf)(x){(Me3Si)(2)N} M{(mu(3)-N)(mu(3)-NH)(2)Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}] (M = Mg, x = 0; Ca, x = 1) with one equivalent of anilines NH2Ar in toluene affords the arylamido complexes [(ArHN) M{(mu(3)-N)(mu(3)- NH)(2)Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)}](n) [M = Mg ( 3), n = 1, Ar = 4-MeC6H4; Ca (4), n = 2, Ar = 2,4,6-Me3C6H2]. The magnesium complex 3 has a single-cube structure whereas the X-ray crystal structure of the analogous calcium derivative 4 shows two cube-type azaheterometallocubane moieties "Ca{(mu(3)-N)(mu(3)- NH)(2)Ti-3(eta(C5Me5)-C-5) (3)(mu(3)-N)}" held together by two mu-2,4,6-trimethylanilido ligands. Complexes 3 and 4 react with chloroform-d(1) at room temperature to give the metal halide adducts [Cl2M{(mu(3)-NH)(3)Ti-3(eta(5)-C5Me5)(3)(mu(3)- N)}] (M = Mg, Ca). A solution of 3 in n-hexane gave complex [{Mg-2(mu(3)-N)(mu(3)-NH)(5)[ Ti-3(eta(5)- C5Me5)(3)(mu(3)- N)](2)}(mu-NHAr)(3)] which shows three mu-4-methylanilido ligands bridging two [MgTi3N4] cube type cores according to an X-ray crystal structure determination.