Accessing highly linear polyethylenes by 2-(1-aryliminoethyl)-7-arylimino-6,6-dimethylcyclopenta[b]pyridylchromium(iii) chlorides†
Abstract
A series of 2-(1-aryliminoethyl)-7-arylimino-6,6-dimethylcyclopenta[b]pyridylchromium(III) chlorides (aryl = 2,6-Me2Ph (Cr1), 2,6-Et2Ph (Cr2), 2,6-i-Pr2Ph (Cr3), 2,4,6-Me3Ph (Cr4), 2,6-Et2-4-MePh (Cr5)) was synthesized and characterized using FT-IR and elemental analysis, and the molecular structure of complex Cr1 was confirmed by using single-crystal X-ray diffraction to present a distorted octahedral geometry around the chromium center. Upon activation with modified methylaluminoxane (MMAO) or ethylaluminium sesquichloride (EASC), all chromium pre-catalysts exhibit good activities towards ethylene polymerization for the highly linear polyethylene.