Development of a method for the preparation of ruthenium indenylidene-ether olefin metathesis catalysts

Abstract

The reactions between several derivatives of 1-(3,5-dimethoxyphenyl)-prop- 2- yn-1-ol and different ruthenium starting materials [i.e., RuCl 2(PPh 3) 3 and RuCl 2(p-cymene)(L), where L is tricyclohexylphosphine di-t-butylmethylphosphine, dicyclohexylphenylphosphine, triisobutylphosphine, triisopropylphosphine, or tri-npropylphosphine] are described. Several of these reactions allow for the easy, in-situ and atom-economic preparation of olefin metathesis catalysts. Organic precursor 1-(3,5- dimethoxyphenyl)-1-phenyl-prop-2-yn-1-ol led to the formation of active ruthenium indenylidene-ether complexes, while 1-(3,5-dimethoxyphenyl)-prop-2-yn-1-ol and 1-(3,5- dimethoxyphenyl)-1-methyl- prop-2-yn-1-ol did not. It was also found that a bulky and strong α-donor phosphine ligand was required to impart good catalytic activity to the new ruthenium complexes. © 2012 by the authors.