TERMINAL ALKENE MONOISOMERIZATION CATALYSTS AND METHODS

摘要

The invention provides novel catalysts and methods of using catalysts for controlling the position of a double bond and cis/trans-selectivity in isomerization of terminal alkenes to their 2-isomers. Catalysts such as (pentamethylcyclopentadienyl)Ru formulas 1 and 3 having a bifunctional phosphine can be used in the methods. A catalyst loading of 1 mol % of formulas 1+3 can be employed for the production of (E)-2-alkenes at 40-70° C.; lower temperatures can be used with higher catalyst loading. Acetonitrile-free catalysts can be used at lower loadings, room temperature, and in less than a day to accomplish the same results as catalysts 1+3. The novel catalyst systems minimize thermodynamic equilibration of alkene isomers, so that the trans-2-alkenes of both non-functionalized and functionalized alkenes can be generated.

主权项

1. An alkene isomerization catalyst of Formula I, Formula II, Formula III, Formula IV, or a combination thereof:wherein
each RP is independently a branched (C3-C10)-alkyl, (C3-C10)-cycloalkyl, (C3-C15)-alkenyl, (C2-C12)-alkynyl, heterocyclyl, or an optionally substituted aryl or heteroaryl; each RL is independently a neutral or anionic ligand, or is absent; each RA, RB and RC is independently hydrogen, a branched or linear (C1-C20)-alkyl, (C3-C10)-cycloalkyl, (C3-C15)-alkenyl, (C2-C12)-alkynyl, heterocyclyl, or an optionally substituted aryl or heteroaryl; and X− is a suitable counterion.