Highly active and stereospecific polymerizations of 1,3-butadiene by using bis(benzimidazolyl)amine ligands derived Co(II) complexes in combination with ethylaluminum sesquichloride

Synthesis, characterization, and butadiene polymerization of iron(III), iron(II) and cobalt(II) chlorides bearing 2,6-bis(2-benzimidazolyl)pyridyl or 2,6-bis(pyrazol)pyridine ligand

“…The exceptional performance of such ligand set in olefin polymerization may also be relevance to butadiene area and catalytic performance of transition metals bearing such set of ligands for butadiene polymerization, however, is less established [12,13,15,62,63]. We have reported the high active 2,6-bis(imino)pyridyl ligands ligated transition complexes for selectivity-controlled polymerization of butadiene [39,42,43], and found the selectivity could be manipulated within a wide range, from high cis-1,4 (97.0%) to high trans-1,4 (95.4%) just by either altering the metal center or modifying the ligand environments.…”

Highly active and trans-1,4-specific polymerization of 1,3-butadiene catalyzed by bis(benzimidazolyl)amine chromium complexes activated with methylaluminoxane

“…The bis(benzimidazolyl)amine ligand 1 was prepared by condensation reaction of 1,2-phenylenediamine and methyliminodiacetic acid in ethylene glycol at 190 o C. 11 The ligands 2a and 2b were obtained in high yields through simple N-alkylation by corresponding alkyl halides via sodium salts of 1 in THF. 12 All of these ligands synthesized were confirmed by elemental analysis and NMR spectroscopy.…”

Tunable regioselectivity in 1,3-butadiene polymerization by using 2,6-bis(dimethyl-2-oxazolin-2-yl)pyridine incorporated transition metal (Cr, Fe and Co) catalysts

“…In this respect, there has been increasing interests in the applications of N-O [21,[34][35], SOOS [31], P-P [36][37][38], and pincer ligand N,N,X (X = N, P and C) [22,23,[39][40][41] covering over a broad range of catalytic reactions, in particular, catalyzing diene with polar monomers, as such straightforwards access to a new family of functional rubber materials.…”