文摘
After searching for the proper catalyst, the dual challenges of controlling the position of the double bond, and cis/trans-selectivity in isomerization of terminal alkenes to their 2-isomers are finally met in a general sense by mixtures of (Cb>5b>Meb>5b>)Ru complexes <b>1b> and <b>3b> featuring a bifunctional phosphine. Typically, catalyst loadings of 1 mol % of <b>1b> and <b>3b> can be employed for the production of (E)-2-alkenes at 40鈥?0 掳C. Catalyst comprising <b>1b> and <b>3b> avoids more than any other known example the thermodynamic equilibration of alkene isomers, as the trans-2-alkenes of both nonfunctionalized and functionalized alkenes are generated.