Zur Kinetik der Halcon-Reaktion

The Kinetics of the Halcon Reaction We have investigated the influence of all types of reaction products on the rate of the Halcon reaction. The experiments show that the retarding effect of epoxide is higher than that of the alcohol. Furthermore we have found that the consecutive products of the epoxide retard the Halcon reaction more than the primary reaction products. The reaction rate can be described by an equation of the Michaelis-Menten-type. We determined the initial reaction rate in dependence on the starting concentration on the reaction products.     

Kinetik und Mechanismus der Reaktion von Arylisocyanaten mit Alkylhydroperoxiden

Kinetics and Mechanism of the Reaction of Aryl Isocyanates with Alkyl Hydroperoxides Sec-alkyl peroxycarbamates, prepared from phenyl isocyanate and sec-alkyl hydroperoxides, are instable at normal temperatures and decompose to yield ketones, carbon dioxide and aniline which reacts further to diphenylurea. The reactions of phenyl isocyanate with tetraline hydroperoxide, t-butyl hydroperoxide, aniline, and tert.-butanol in dioxane have been studied kinetically and the catalytic constants of diazabicyclooctane, triethylamine, and stannous octoate as catalysts have been determined. Rate constants of the reactions with hydroperoxides decrease with increasing hydroperoxide concentration caused by association of the catalyst with the hydroperoxide. Compared to their basicities, alkyl hydroperoxides are very reactive towards isocyanates.