申请人:Ciba-Geigy Corporation
公开号:US04282358A1
公开(公告)日:1981-08-04
Substituted N-methylbenzoxazines of the formula ##STR1## wherein the ring A can also contain a nitrogen atom as ring member, each of R.sub.1 and R.sub.3 independently is hydrogen, lower alkyl, halogen, nitro or trifluoromethyl, each of R.sub.2 and R.sub.4 independently is hydrogen or halogen and each of m and n is an integer from 1 to 3, are obtained by cyclizing compounds of the formula ##STR2## wherein A, R.sub.2, R.sub.4, m and n are as defined above, R is chlorine or bromine, and each of R.sub.1 ' and R.sub.3 ' independently is hydrogen, lower alkyl, halogen or trifluoromethyl, in the presence of dimethylmethanephosphonate, at reflux temperature, and, if desired, nitrating the resultant compounds.
根据上述公式,得到的N-甲基苯并噁嗪的替代物,其中环A还可以包含一个氮原子作为环成员,R.sub.1和R.sub.3中的每一个独立地是氢、较低的烷基、卤素、硝基或三氟甲基,R.sub.2和R.sub.4中的每一个独立地是氢或卤素,m和n中的每一个是1到3之间的整数,通过在二甲基甲磷酸酯存在下,于回流温度下,环化上述公式的化合物而获得,其中A、R.sub.2、R.sub.4、m和n如上所定义,R是氯或溴,R.sub.1'和R.sub.3'中的每一个独立地是氢、较低的烷基、卤素或三氟甲基,并且如果需要,对所得化合物进行硝化。