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Reactions of Ti(NMe(2))(2)Cl(2) with a wide range of primary alkyl and arylamines RNH(2) afforded the corresponding 5-coordinate imido titanium compounds Ti(NR)Cl(2)(NHMe(2))(2) (R = (t)Bu (1), (i)Pr (2), CH(2)Ph (3), Ph (4), 2,6-C(6)H(3)Me(2) (5), 2,6-C(6)H(3)(i)Pr(2) (6), 2,4,6-C(6)H(2)F(3) (7), 2,3,5,6-C(6)HF(4) (8), C(6)F(5) (9), 4-C(6)H(4)Cl (10), 2,3,5,6-C(6)HCl(4) (11), 2-C(6)H(4)CF(3) (12), 2-C(6)H(4)(t)Bu (13)). The compounds 1-13 are monomeric in solution but in the solid state form either N-H...Cl hydrogen bonded dimers or chains or perfluorophenyl pi-stacked chains, depending on the imido R-group. The compound 13 was also prepared in a "one-pot" synthesis from RNH(2) and Ti(NMe(2))(4) and Me(3)SiCl. Reaction of certain Ti(NR)Cl(2)(NHMe(2))(2) compounds with an excess of pyridine afforded the corresponding bis- or tris-pyridine analogues [Ti(NR)Cl(2)(py)(x)](y) (x = 3, y = 1; x = y = 2), and the structure of Ti(2)(NC(6)F(5))(2)Cl(2)(mu-Cl)(2)(py)(4) shows pi-stacking of perfluorophenyl rings. Reaction of Ti(NMe(2))(2)Cl(2) with cross-linked aminomethyl polystyrene gave quantitative conversion to the corresponding solid-supported titanium imido complex. This paper represents the first detailed study of how supramolecular structures of imido compounds may be influenced by simple variation of the imido ligand N-substituent.

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The multigram syntheses of the protio ligands (2-NC(5)H(4))CH(2)N(CH(2)CH(2)NHSiMe(2)R)(2) (R = Me, H(2)N(2)NN' 3; R = (t)Bu, H(2)N(2)NN() 4) are described via reactions of the previously reported (2-NC(5)H(4))CH(2)N(CH(2)CH(2)NH(2))(2) (1). A new synthesis of 1 is reported starting from 2-aminomethylpyridine and N-tosylaziridine, proceeding via (2-NC(5)H(4))CH(2)N(CH(2)CH(2)NHTs)(2) (2). Reaction of H(2)N(2)NN' or H(2)N(2)NN* with (n)BuLi gives good yields of the dilithiated derivatives Li(2)N(2)NN' and Li(2)N(2)NN*. Reaction of H(2)N(2)NN' or H(2)N(2)NN* with [MCl(2)(CH(2)SiMe(3))(2)(Et(2)O)(2)] gives the cis-dichloride complexes [MCl(2)(L)] (L = N(2)NN', M = Zr 7 or Hf 8; L = N(2)NN(), M = Zr 9). The corresponding reactions of H(2)N(2)NN' or H(2)N(2)NN* with [Zr(NMe(2))(4)] afford the bis(dimethylamide) derivatives [Zr(NMe(2))(2)(L)] (L = N(2)NN' 10 or N(2)NN* 11). All of these protonolysis reactions proceed smoothly and in good yields. Attempts to prepare the titanium complexes [Ti(X)(2)(N(2)NN')] (X = Cl or NMe(2)) were unsuccessful. The X-ray crystal structures of (2-NC(5)H(4))CH(2)N(CH(2)CH(2)NHTs)(2).EtOH, [ZrCl(2)(N(2)NN')].0.5C(6)H(6), [Zr(NMe(2))(2)(N(2)NN')], and [Zr(NMe(2))(2)(N(2)NN*)] are reported.

Reactions of 1,4-dimethyl-1,4,7-triazacyclononane (L1a) and 1,4-diisopropyl-1,4,7-triazacyclononane (L1b) to form 1-aminopropyl-4,7-di-R-1,4,7-triazacyclononane [R = Me (H2L3a) or Pri (H2L3b)] and 1-(2-aminobenzyl)-4,7-di-R-1,4,7-triazacyclononane [R = Me (H2L5a) or Pri (H2L5b)] are reported. Reaction of H2L3a and H2L5a with [Ti(NMe2)2Cl2] gives the ansa-linked macrocycle-imido complexes [Ti(kappa 4-L3a)Cl2] (5a) and [Ti(kappa 4-L5a)Cl2] (6a), respectively, and NHMe2. Reaction of H2L3a with [Ti(NBut)Cl2(py)3] gives [Ti(NBut)(kappa 3-H2L3a)Cl2] (7), which possesses a pendant alkylamine group that does not undergo amine/tert-butylimido group exchange to give 5a and ButNH2. However, reaction of H2L3b and H2L5b with [Ti(NBut)Cl2(py)3] does give amine/tert-butylimido group exchange to form [Ti(kappa 4-L3b)Cl2] (5b), [Ti(kappa 4-L5b)Cl2] (8b), and ButNH2. The compounds 5a,b and 6a,b are isolobal analogues of group 4 ansa-metallocene complexes and relatives of titanium cyclopentadienyl-amido constrained geometry olefin polymerization catalysts. Reaction of 5b with AgOTf affords [Ti(kappa 4-L3b)(OTf)Cl] (8) as the major product, the crystal structure of which has been determined. Alkylation of 6b by RLi gives the dialkyl derivatives [Ti(kappa 4-L5b)(R)2] [R = Me (9) or CH2SiMe3 (10)]. The ethylene polymerization capability of the compounds 5a,b, 6a,b, and 10 in the presence of methylaluminoxane has been determined and compared to that of [Ti(NBut)(kappa 3-L1a,b)Cl2] (11a,b); in all instances, low yields of high-molecular-weight polymer are obtained.