- Highly Z-selective metathesis homocoupling of terminal olefins.
Highly Z-selective metathesis homocoupling of terminal olefins.
Journal of the American Chemical Society (2009-11-19)
Annie J Jiang, Yu Zhao, Richard R Schrock, Amir H Hoveyda
PMID19919135
ABSTRACT
Mo and W MonoAryloxide-Pyrrolide (MAP) olefin metathesis catalysts can couple terminal olefins to give as high as >98% Z-products in moderate to high yields with as little as 0.2% catalyst. Results are reported for 1-hexene, 1-octene, allylbenzene, allyltrimethylsilane, methyl-10-undecenoate, methyl-9-decenoate, allylB(pinacolate), allylOBenzyl, allylNHTosyl, and allylNHPh. It is proposed that high Z-selectivity is achieved because a large aryloxide only allows metallacyclobutanes to form that contain adjacent cis substituents and because isomerization of Z-product to E-product can be slow in that same steric environment.
MATERIALI