Molecular organization of reactants in the kinetics and catalysis of liquid phase reactions: X. Synergism in the combined catalysis of urethane formation by organotin compounds and tertiary amines

The kinetics of the reaction of m-Cl-phenyl isocyanate with n-butanol in he ptane catalyzed by tin tributylacetate and diazobicyclooctane is studied. T he phenomenon of synergism in the catalysis of urethane formation is quanti tatively described by the simulation of kinetics using the data on the equi librium constants of association of the alcohol in the system and modern co ncepts on the reaction mechanism. The formation of a donor-acceptor complex between the catalysts and inclusion of this complex into the composition o f new reactive heteroassociates with the participation of the monomeric and dimeric forms of the alcohol were the reasons for the nonadditive action o f the catalysts in the reaction under study.