Marinescu Smaranda C, Schrock Richard R, Müller Peter, Hoveyda Amir H
Department of Chemistry 6-331, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
J Am Chem Soc. 2009 Aug 12;131(31):10840-1. doi: 10.1021/ja904786y.
Monoaryloxide-pyrrolide (MAP) olefin metathesis catalysts of molybdenum that contain a chiral bitetralin-based aryloxide ligand are efficient for ethenolysis of methyl oleate, cyclooctene, and cyclopentene. Ethenolysis of 5000 equiv of methyl oleate produced 1-decene (1D) and methyl-9-decenoate (M9D) with a selectivity of >99%, yields up to 95%, and a TON (turnover number) of 4750 in 15 h. Tungstacyclobutane catalysts gave yields approximately half those of molybdenum catalysts, either at room temperature or at 50 degrees C, although selectivity was still >99%. Ethenolysis of 30,000 equiv of cyclooctene to 1,9-decadiene could be carried out with a TON of 22,500 at 20 atm (75% yield), while ethenolysis of 10,000 equiv of cyclopentene to 1,6-heptadiene could be carried out with a TON of 5800 at 20 atm (58% yield). There is no reason to propose that the efficiency of ethenolysis has been maximized with the most successful catalyst reported here.
含有基于手性双四氢萘的芳氧基配体的钼单芳氧基-吡咯啉(MAP)烯烃复分解催化剂,对于油酸甲酯、环辛烯和环戊烯的乙烯解反应是有效的。5000当量油酸甲酯的乙烯解反应在15小时内生成1-癸烯(1D)和9-癸烯酸甲酯(M9D),选择性>99%,产率高达95%,转换数(TON)为4750。尽管选择性仍>99%,但钨环丁烷催化剂在室温或50℃下的产率约为钼催化剂的一半。30000当量环辛烯乙烯解生成1,9-癸二烯,在20个大气压下(产率75%),TON为22500;而10000当量环戊烯乙烯解生成1,6-庚二烯,在20个大气压下(产率58%),TON为5800。没有理由认为此处报道的最成功的催化剂已使乙烯解反应的效率最大化。