Carboranylimine-complexed titanium (IV) organometallics: An investigation of synthesis, structure and catalytic polymerization

The condensation reaction of carboranylmethyl ammonium chloride, 1-(CH2NH3Cl)-1,2-C2B10H11 (1) with phenyl aldehydes produced phenyl(carboranylmethyl)imine ligands, 1-(CH2N = CC6H4R-2)-1,2-C2B10H11 (2 R = H; 3 R = OH). Deprotonation of 2 and 3 with n-BuLi followed by metalation with TiCl4 led to the formation of phenyl(carboranylmethyl)imidotitanium (IV) chlorides, [1-(CH2N = CC6H4R-2)-1,2-C2B10H10]TiCl3 (4 R = H; 5 R = O). Compounds 4 and 5 were found to catalyze the polymerization of ethylene in the presence of co-catalyst MAO to produce high molecular weight polyethylene. In addition, compounds 4 and 5 were also active for copolymerization of ethylene and methyl-10-undecannoate to generate corresponding copolymers.

Graphical abstractTitanium(IV) organometallics incorporating carboranylimine ligands were synthesized and fully characterized. These organometallic complexes were found to be active catalysts for polymerization of ethylene and methyl-10-undecannoate.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Carborane-based imine ligands were synthesized and coordinated with titanium. ► Polyethylenes with high molecular weight were produced by the catalysts. ► Copolymers of ethylene/methyl-10-undecannoate were produced by the catalysts.