New Diamide−Diamine Ligands and their Zirconium and Hafnium Dichloride and Bis(dimethylamide) Complexes
- 7 February 2002
- journal article
- research article
- Published by American Chemical Society (ACS) in Inorganic Chemistry
- Vol. 41 (5) , 1110-1119
- https://doi.org/10.1021/ic011043z
Abstract
The multigram syntheses of the protio ligands (2-NC5H4)CH2N(CH2CH2NHSiMe2R)2 (R = Me, H2N2NN‘ 3; R = tBu, H2N2NN*4) are described via reactions of the previously reported (2-NC5H4)CH2N(CH2CH2NH2)2 (1). A new synthesis of 1 is reported starting from 2-aminomethylpyridine and N-tosylaziridine, proceeding via (2-NC5H4)CH2N(CH2CH2NHTs)2 (2). Reaction of H2N2NN‘ or H2N2NN* with nBuLi gives good yields of the dilithiated derivatives Li2N2NN‘ and Li2N2NN*. Reaction of H2N2NN‘ or H2N2NN* with [MCl2(CH2SiMe3)2(Et2O)2] gives the cis-dichloride complexes [MCl2(L)] (L = N2NN‘, M = Zr 7 or Hf 8; L = N2NN*, M = Zr 9). The corresponding reactions of H2N2NN‘ or H2N2NN* with [Zr(NMe2)4] afford the bis(dimethylamide) derivatives [Zr(NMe2)2(L)] (L = N2NN‘ 10 or N2NN*11). All of these protonolysis reactions proceed smoothly and in good yields. Attempts to prepare the titanium complexes [Ti(X)2(N2NN‘)] (X = Cl or NMe2) were unsuccessful. The X-ray crystal structures of (2-NC5H4)CH2N(CH2CH2NHTs)2·EtOH, [ZrCl2(N2NN‘)]·0.5C6H6, [Zr(NMe2)2(N2NN‘)], and [Zr(NMe2)2(N2NN*)] are reported.Keywords
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