Abstract: There is disclosed a new process for the epoxidization of olefins by reaction with hydrogen peroxide according to the double phase technique with "onium" salts, characterized in that the reaction is conducted in a liquid aqueous-organic biphasic system consisting of:(a) an organic phase substantially containing the olefin, and(b) an aqueous acid phase substantially containing hydrogen peroxide,in the presence of a catalytic system consisting of a first component which is at least one element selected from W. Mo, V or at least one derivative of said elements, and of a second component which is at least one derivative selected from the derivatives of P and As.

Abstract: A process is disclosed for the carboxylation of organic substrates or reactants containing at least one active hydrogen atom by reaction with CO.sub.2 and alkaline phenates in an organic medium, characterized in that the reaction is conducted in the presence of simple or substituted alkaline phenates in at least an aprotic medium which is at least a partial solvent for the phenate, and selected from the class consisting of cyclic ethers, aliphatic, cycloaliphatic and heterocyclic tertiary amines, and cyclic sulphones, and at temperatures between about 40.degree. and 60.degree. C. The alkaline phenate is selected from the class consisting of the Li, Na, K salts of the phenols of the general formula: ##STR1## WHEREIN R is hydrogen or an alkyl or an alkoxy group, linear or branched, having up to 20 carbon atoms, or a phenyl group, n varies from 1 to 5, and M is the alkali metal. The starting organic substrate or reactant is selected from the class consisting of ketones, esters, nitroparaffins and nitriles.