申请人:Zambon S.p.A.
公开号:US04772719A1
公开(公告)日:1988-09-20
A novel process for the preparation of 3-bromo- and 3-chloro-5-substituted isoxazoles is provided. Dibromo- or dichloro-formaldoxime is reacted with an excess of an 1-alkyne derivative of the formula R--C.tbd.CH where R is hydrogen, phenyl or 1-6 C alkyl optionally substituted by halogen, OH, OR', CHO, COR', COOR', CONH.sub.2, CONR'R" or NHCOR' where, in turn, R' and R", which may be the same or different, are a 1-6 C alkyl or haloalkyl, in the presence of (i) at least an equimolecular amount, with respect to the dibromo- or dichloro-formaldoxime, of an alkaline base selected from the class consisting of sodium and potassium carbonate and bicarbonate and (ii) an inert solvent in which the 1-alkyne is soluble at room temperature.
提供了一种制备3-溴-和3-氯-5-取代异噁唑的新工艺。在(i)至少等摩尔量的碱性碳酸钠和碳酸氢钾的类别中选择碱性碱,与二溴甲酰肟或二氯甲酰肟一起,在惰性溶剂中,在室温下与化学式为R-C.tbd.CH的1-炔基衍生物的过量反应,其中R为氢,苯基或1-6 C烷基,可选地被卤素,OH,OR',CHO,COR',COOR',CONH.sub.2,CONR'R"或NHCOR'取代,其中R'和R"可以相同或不同,是1-6 C烷基或卤代烷基。