1332768-08-7Relevant academic research and scientific papers
Mono N,C,N-pincer complexes of titanium, vanadium and niobium. Synthesis, structure and catalytic activity in olefin polymerisation
Chuchuryukin, Alexey V.,Huang, Rubin,Van Faassen, Ernst E.,Van Klink, Gerard P. M.,Lutz, Martin,Chadwick, John C.,Spek, Anthony L.,Van Koten, Gerard
, p. 8887 - 8895 (2011/10/09)
Transmetallation of 4,4′-bis{(2,6-bis[(dimethylamino)methyl] phenylgold)diphenyl-phosphino}biphenyl (3) with MCl4 (M = Ti, NbCl, V) in benzene gave the corresponding transition metal pincer complexes (4) and insoluble 4,4′-bis[P-(chloro gold(i))diphenylphosphino]biphenyl (2), which can be quantitatively recovered and recycled. Interestingly, 3 did not react with TiCl3. However, reaction of 2,6-bis[(dimethylamino)methyl] phenyllithium (1) with TiCl3 resulted in formation of the novel diaryltitanium(iv) compound 5 (16% yield), comprising one N,C,N-mer bound NCN-pincer ligand and a second NCN-pincer ligand that is rearranged from a 1,2,6-isomer to a 1,2,4 one. The latter NCN-ligand is dianionic and is bidentate bonded; one of the CH2NMe2 substituents (para to C′ipso) is non-coordinated, while the second CH 2NMe2 group, after C-H activation of one of the Me groups, is η2-C,N-bonded to the titanium centre trans to C ipso of the mer-NCN ligand. The new NCN-pincer metal complexes 2,6-bis[(dimethylamino)methyl]phenylTiCl3 (4a) and 2,6-bis[(dimethylamino)methyl]-phenylVCl2 (4d) gave, after immobilization on MgCl2-based supports, very high activity in ethene polymerisation. The Royal Society of Chemistry 2011.
