Novel semicyclic 3-aryl-3-chloro-2-propeniminium perchlorates 6 are synthesized by treating semicyclic enaminones 1 (2-aroylmethylene-1-methylpyrrolidines, -piperidines and -azepanes) with phosphoryl chloride dimethylformamide. Reaction of these chloropropeniminium salts 6 with hydrazines 2 give regiospecifically either 3-(Ï-aminoalkyl)- or 5-(Ï-aminoalkyl)pyrazoles 5 or 10. The direction of these ring transformation reactions is governed by the nature of substituent of the hydrazine. The synthesis is especially useful in the preparation of 1-substituted 5-(Ï-aminoalkyl)pyrazoles 10.
新型半环 3-芳基-3-
氯-2-
丙烯亚胺高氯酸盐 6 是通过用二甲基甲酰胺
磷酰
氯处理半环烯酮 1(2-芳基亚甲基-
1-甲基吡咯烷、-
哌啶和-氮杂
环庚烷)而合成的。这些
氯丙烯亚胺盐 6 与
肼 2 反应后,可以得到 3-(Ï-
氨基烷基)- 或 5-(Ï-
氨基烷基)
吡唑 5 或 10。 这些环转化反应的方向受
肼的取代基性质的影响。该合成方法尤其适用于制备 1-取代的 5-(Ï-
氨基烷基)
吡唑 10。