Baeyer-Villiger oxidation of cyclic ketones with hydrogen peroxide catalyzed by cationic complexes of platinum(II): selectivity properties and mechanistic studies

摘要: The catalytic oxidation of simple cyclic ketones with hydrogen peroxide to give the corresponding lactones is reported. reaction catalyzed by complexes Pt(II) type [(P-P)Pt(CF[sub 3])(solv)][sup +] (P-P = diphosphine) that may be deactivated hydroxy acids formed hydrolysis lactones. selectivity catalyst studied in substrates like camphor, 2-cyclohexene-1-one, menthone, carvone, and indanones. Cyclobutanone used determine mechanism from initial rates studies. scheme proposed, which accounts for observed effects various reactants, involves coordination ketone on vacant site complex followed nucleophilic attack free carbonyl carbon. involvement a quasi-peroxymetallacyclic intermediate suggested rearranges lactone starting complex. A comparison mechanistic behavior organic peroxy given. 24 refs., 10 figs., 3 tabs.