A process for the preparation of a 3-bromo-4-fluoro-benzaldehyde acetal of the formula: ##STR1## in which R each independently is a C.sub.1 to C.sub.4 alkyl group or the radicals R together are a C.sub.2 to C.sub.5 alkanediyl radical, comprising reacting 3-bromo-4-fluoro-phenylglyoxylic acid of the formula: ##STR2## with an amine of the formula: H.sub.2 N--R.sup.1 in which R.sup.1 is an alkyl, cycloalkyl or aryl radical, at a temperature between about 0.degree. and 200.degree. C. to produce a 3-bromo-4-fluoro-benzaldimine of the formula: ##STR3## and reacting that with an alcohol or alkanediol of the formula: (HO).sub.n --R in which n is 1 or 2 in the presence of sulphuric acid at a temperature between about 0.degree. and 100.degree. C. Various of the reactants are new and syntheses are given.
一种制备
3-溴-4-氟苯甲醛缩醛的方法,其
化学式为:##STR1## 其中,R分别是C.sub.1至C.sub.4烷基或基团R共同是C.sub.2至C.sub.5的烷二基基团,包括将3-溴-4-
氟苯甘酸(
化学式如下:##STR2##)与
化学式为H.sub.2N--R.sup.1的胺反应,其中R.sup.1是烷基、环烷基或芳基基团,在温度约为0℃至200℃之间,以产生
3-溴-4-氟苯甲醛亚胺(
化学式如下:##STR3##),并在
硫酸的存在下,将其与
化学式为(HO).sub.n --R的醇或烷二醇反应,其中n为1或2,反应温度在约0℃至100℃之间。其中多种反应物是新的,给出了合成方法。