文摘
Isomerization of N-allylamides catalyzed by ruthenium and rhodium complexes to corresponding 1-propenyl derivatives is described. The first catalytic system containing a precursor ({[RuCl2(1,5-COD)]x}), tris(2,4-di-t-butylphenyl)phosphite and CaH2 for highly (Z)-selective isomerization of allylamides is presented. It has been shown that the double bond migration catalyzed by the investigated catalytic systems occurs according to the hydride mechanism. The participation of ortho-metallation from precursor and triphenylphosphine in the formation of hydride complex has been proved. It is proposed that the observed (Z)-selectivity of the isomerization of some allylamides is the result of the steric effect in the transition state. The application of siliceous mesoporous cellular foams for an effective removal of the catalyst from the post-reaction mixture is described.