Isomerization of allyl aryl ethers to their 1-propenyl derivatives catalysed by ruthenium complexes

The results of double-bond migration in allyl aryl ethers catalysed by ruthenium complexes, mainly by [RuClH(CO)(PPh3)(3)] have been presented. The conversion of allyl to 1-propenyl ethers is quantitative. High E/Z selectivity of some 1-propenyl ethers has been achieved by the application of [RuCl2(COD)](x) + PR3 catalytic system (also with addition of inorganic hydrides). An explanation of E/Z selectivity control based on transition state of beta-elimination has been proposed. The results are supplemented with elements of coordination effects of reactants, solvent influence and catalyst activity on chosen models. Separation of the 1-propenyl ethers might be achieved by simple techniques-distillation or crystallization. Moreover, it has been shown that less stable products, such as (4-aminophenyl) (1-propenyl) ether, might be separated from the reaction mixture using functionalized siliceous mesoporous cellular foams. (C) 2004 Elsevier B.V. All rights reserved.