Isotope exchange of heterocyclic compounds with D2O in the presence of transition metals

During a study of deuterium-hydrogen exchange of two-ring condensed heterocycles in the presence of a Pt catalyst it was observed that the degree of deuteration decreases in the order benzofuran naphthalene > benzothiophene. It was found that the degree of deuteration of 2-acetylbenzofuran is 80%, whereas for 2-propylbenzofuran it is only 8%. The degree of deuteration of hydrogenated derivatives decreases in the order coumarin > chromene > dihydrocoumarin; the formation of polydeuterated derivatives is observed for coumarin, whereas products of replacement of one hydrogen atom by deuterium predominate for chromene and dihydrocoumarin.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 451–453, April, 1981.