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.
从N-苯甲基邻苯二甲
酰亚胺开始,通过两个步骤制备稳定的亚硝基自由基(I)。在第一步中,使用在
甲基叔丁基醚中制备的Grignard试剂对N-苯甲基邻苯二甲
酰亚胺进行处理,制备中间体N-苯甲基-1,1,3,3-四烷基
异吲哚啉。在同一反应环境中,通过
邻苯二甲酸酐和苯
甲胺制备N-苯甲基邻苯二甲
酰亚胺。在第二步中,将N-苯甲基-1,1,3,3-四烷基
异吲哚啉通过氢解和
过氧化氢的氧化,在多
钼酸或多
钨酸的酸和盐催化剂的存在下转化为亚硝基自由基。