Ring-Transformation von Imidazolidin-2,4-dionen (= Hydantoinen) zu 4H-Imidazolen bei der Umsetzung mit 3-(Dimethylamino)-2,2-dimethyl-2H-azirin

Abstract

Ring Transformation of Imidazolidine-2,4-diones (= Hydantoins) to 4H-Imidazoles in the Reaction with 3-(Dimethylamino)-2,2-dimethyl-2H-azirines. At ca. 70°, 3-(dimethylamino)-2,2-dimethyl-2H-azirin (1e) and 5,5-disubstituted hydantoins 4 in MeCN or i-PrOH give 2-(1-aminoalkyl)-5-(dimethylamino)-4,4-dimethyl-4H-imidazoles 5 in good yield (Scheme 2). These products are decarboxylated 1:1 adducts of 1 and 4. A reaction mechanism is suggested in analogy to the previously reported reactions of 1 and NH-acidic heterocycles containing the CO Show more