申请人:Bayer Aktiengesellschaft
公开号:US04383949A1
公开(公告)日:1983-05-17
A process for the preparation of a 3-bromo-4-fluorobenzaldehyde acetal of the formula ##STR1## in which R.sup.1 is methyl or ethyl, which comprises reacting a 3-bromo-4-fluoro-benzoic acid halide with ammonia to form 3-bromo-4-fluoro-benzoic acid amide, dehydrating said amide to form 3-bromo-4-fluoro-benzonitrile, reacting the nitrile with formic acid in the presence of a catalyst at a temperature between about 0.degree. and 150.degree. C. to form 3-bromo-4-fluorobenzaldehyde, and reacting said aldehyde with R.sup.1 OH or a derivative thereof capable of forming an acetal. The amide and nitrile are new compounds. The acetals are known intermediates in the synthesis of pyrethroid-like insecticides.
一种制备式为##STR1##的3-溴-4-氟苯甲醛缩醛的方法,其中R.sup.1是甲基或乙基,包括将3-溴-4-氟苯甲酸卤化物与氨反应以形成3-溴-4-氟苯甲酸酰胺,脱水所述酰胺以形成3-溴-4-氟苯甲腈,将所述腈与甲酸在催化剂的存在下在温度约为0℃至150℃之间反应以形成3-溴-4-氟苯甲醛,并将所述醛与R.sup.1 OH或能形成缩醛的衍生物反应。所述酰胺和腈是新的化合物。缩醛是合成拟除虫菊酯类杀虫剂的已知中间体。