申请人:Bayer Aktiengesellschaft
公开号:US04348538A1
公开(公告)日:1982-09-07
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:在该化学式中,R分别是C.sub.1到C.sub.4烷基或者R基共同是C.sub.2到C.sub.5的烷二基基团,包括将3-溴-4-氟苯甘酸(化学式如下:)与一种化学式为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0到200摄氏度之间,生成一种3-溴-4-氟苯甲醛亚胺(化学式如下:),然后在硫酸存在下,在温度约0到100摄氏度之间,将其与一种醇或烷二醇(化学式为(HO).sub.n --R,其中n为1或2)反应。其中,多种反应物均为新的,给出了合成方法。