title: Synthesis and structural analysis of (imido)vanadium(V) complexes containing chelate (anilido)methyl-imine ligands: ligand effect in ethylene dimerization.
abstract: A series of (imido)vanadium dichlorido complexes containing chelate anionic donor ligands of the type, VCl2(L)(NR) [R = 1-adamantyl (Ad), L = 2-(2,6-Me2C6H3)NCH2(C9H6N) (2), 8-(2,6-Me2C6H3)NCH2(C9H6N) (3); L = 2-(2,6-R'2C6H3)NCH2(C5H4N), R = 2-MeC6H4, R' = Me (4a), (i)Pr (4b); L = 2-(2,6-Me2C6H3)NCH2(C5H4N), R = 4-MeC6H4 (5), 3,5-Me2C6H3 (6)], have been prepared and identified. The reactions with ethylene by 2,3 in the presence of methylaluminoxane (MAO) afforded a mixture of high molecular weight polyethylene and oligomers. Reactions with ethylene by VCl2[2-(2,6-R'2C6H3)NCH2(C5H4N)](NAd) (1a,b), 4-6 afforded 1-butene with high selectivities (>92%), and the activities by 4a,b are at the same level as those in 1a,b. The activities by 5,6 were lower than 4a,b and were at the same level of that by VCl2[2-(2,6-Me2C6H3)NCH2(C5H4N)](NPh). These results thus suggest that both the chelate anionic donor and the imido ligands play a role for both the activity and the selectivity.
authors: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami Osawa, Hachioji, Tokyo 192-0397, Japan. ktnomura@tmu.ac.jp
authors: Kotohiro
authors: K
authors: Nomura
authors: Atsushi
authors: A
authors: Igarashi
authors: Shohei
authors: S
authors: Katao
authors: Wenjuan
authors: W
authors: Zhang
authors: Wen-Hua
authors: WH
authors: Sun
mesh_terms: D000813:Anilides / Q000737:chemistry*; D019281:Dimerization; D005030:Ethylenes / Q000138:chemical synthesis* / Q000737:chemistry; D007094:Imides / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D014639:Vanadium / Q000737:chemistry*
chemical_list: D000813:Anilides; D005030:Ethylenes; D007094:Imides; D007097:Imines; D008024:Ligands; D009942:Organometallic Compounds; D014639:Vanadium