Sur l'amino‐5‐benzoyl‐4‐méthyl‐3‐isoxazole: synthèse et transformation en dihydro‐6,8‐diméthyl‐3,8‐phényl‐4‐<i>7H</i>‐isoxazolo[5,4‐<i>e</i>]diazépin‐1,4‐one‐7

Abstract

Abstract On treatment with ammonia and benzaldehyde the benzalisoxazolone 3 does not give the aminoketone 7 as assumed by Speroni [ 1 ] but a product which has been shown to be identical with the enamine 8 prepared by Ried &amp; Czack [4] from ethyl oximinoacetoacetate and benziminoethyl ether. Authentic aminoketone 7 was synthesized in a three‐step procedure starting from the aminonitrile 19 . Conversion of 7 into the bromacetyl derivative 23 and subsequent treatment with hexamethylene‐tetramine yielded the isoxazolodiazepine 24 . Methylation of 24 with diazomethane produced predominantly the N‐methyl derivative 1 along with a small amount of the O‐methyl compound 25 .