3,3-Dimethyl-cyclopropane-1,1,2-tricarboxylic acid derivatives of the formula ##STR1## in which R is alkyl, and R.sup.1 and R.sup.2 each is alkoxycarbonyl or cyano, with the proviso that at least one of them is cyano, suitable for use as intermediates in making insecticides, are produced by reacting a .beta.,.beta.-dimethyl-acrylic acid nitrile of the formula ##STR2## with bromine or chlorine at a temperature between about -20.degree. and +50.degree. C. to produce a compound of the formula ##STR3## in which Hal is chlorine or bromine, which compound is further reacted with a malonic acid derivative of the formula ##STR4##
公式为##STR1##的3,3-二甲基
环丙烷-1,1,2-三羧酸衍
生物,其中R是烷基,R.sup.1和R.sup.2分别是烷氧羰基或
氰基,但至少其中一个是
氰基,适用于作为制造
杀虫剂的中间体,通过将公式为##STR2##的β,β-二
甲基丙烯酸腈与
溴或
氯在约-20度至+50度C的温度下反应而生成,得到公式为##STR3##的化合物,其中Hal为
氯或
溴,然后将该化合物进一步与公式为##STR4##的
丙二酸衍
生物发生反应。