摘要 |
Process for the preparation of stable nitroxyl radicals (I) starting from N-benzylphthalimide in two steps. In the first step, the intermediate N-benzyl-1,1,3,3-tetra-alkylisoindoline is prepared by treatment with a Grignard reagent, prepared in methyl-tert-butyl ether, of N-benzylphthalimide, obtained in the same reaction environment starting from phthalic anhydride and benzylamine. In the second step, the N-benzyl-1,1,3,3-tetra-alkylisoindoline is transformed into the nitroxyl radical by hydrogenolysis and subsequent oxidation with hydrogen peroxide in the presence of a catalyst selected from acids and salts of polymolybdic or polytungstic acids.
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