Enhanced Productivity of a Supported Olefin Trimerization Catalyst
journal contributionposted on 04.01.2016, 00:00 by Aaron Sattler, Dinesh C. Aluthge, Jay R. Winkler, Jay A. Labinger, John E. Bercaw
Treatment of dry silica with methylaluminoxane (MAO) followed by (FI)TiCl3 (FI = (N-(5-methyl-3-(1-adamantyl)salicylidene)-2′-(2″-methoxyphenyl)anilinato) gives a heterogeneous supported ethylene trimerization catalyst, s(FI)Ti, which exhibits productivity more than an order of magnitude higher than its homogeneous analogues. This increase in productivity is attributed to a decreased rate of catalyst decomposition, a process that is proposed to occur via comproportionation to an inactive TiIII species; immobilization retards this process. In addition, s(FI)Ti catalyzes trimerization of α-olefins with high selectivity. Based on regioisomer distributions, catalysis by s(FI)Ti involves the same active species as the previously reported homogeneous systems (FI)TiR2Me/B(C6F5)3 (R = Me, CH2SiMe3, CH2CMe3).