Reaction of bis(trifluoromethyl)amino-oxyl with t-butylbenzene, 2,2-diphenylpropane, benzylcyclopropane and some related alcohols

Article abstract of DOI:10.1016/0022-1139(93)02988-Q

Reaction of the oxyl (CF3)2NO(.) (1) with t-butylbenzene (c. 3:1 molar ratio) at room temperature gives the hydroxylamine (CF3)2NOH (3) (43percent on oxyl) and a multicomponent higher-boiling mixture containing the substitution product (CF3)2NOCH2CMe2Ph (3) (28percent on arene), and the compounds 3-(CF3)2NC6H4CMe3 (5) (8percent on arene) and 4-(CF3)2NC6H4CMe3 (6) (6percent on arene).The reaction with 2,2-diphenylpropane (c. 4:1 molar ratio) at 70-80 deg C affords hydroxylamine 3 (45percent on oxyl) and a complex higher-boiling mixture, from which only the substitution product (CF3)2NOCH2CMePh2 (7) (36percent on arene) could be isolated.In contrast, the reaction of oxyl 1 with benzylcyclopropane at room temperature is clean and gives hydroxylamine 3 (49percent on oxyl) and the substitution product (8) (95percent on cyclopropane).From the reactions of oxyl 1 with 2-phenylpropan-2-ol (2:1 molar ratio), cyclopropylmethanol (c. 4:1 molar ratio) and 1-cyclopropylethanol (2:1 molar ratio) at room temperature, apart from hydroxylamine 3, the isolated products are a mixture of dimers of α-methylstyrene (10-12) (30percent on ol) and the 2:1 adduct of oxyl 1 and α-methylstyrene, i.e. (CF3)2NOCH2CMe(Ph)ON(CF3)2 (9) (50percent on ol); the ester (13) (99percent on ol); and the ketone (15) (60percent on ol), respectively.