申请人:Bayer Aktiengesellschaft
公开号:US04292246A1
公开(公告)日:1981-09-29
A process for the preparation of a tetrahydrofuran-3-aldehyde of the formula ##STR1## in which R.sup.1 is hydrogen, or an alkyl or phenyl radical, and R.sup.2 is an alkyl, (C.sub.1 -C.sub.4 -alkoxy)-carbonyl, (C.sub.1 -C.sub.4 -alkoxy) carbonylmethylene or phenyl radical, or R.sup.1 and R.sup.2 together are an alkanediyl radical, comprising heating a 4,5-dihydro-1,3-dioxepine of the formula ##STR2## at about 100.degree. to 250.degree. C. in the presence of a catalytic amount of o-toluic acid. Advantageously about 0.05 to 0.15 mole of o-toluic acid is used per mole of the dioxepine, and heating is effected between about 120.degree. and 200.degree. C. at a pressure up to about 10 bars. The compounds, some of which are new, are insecticidally and acaricidally active.
一种制备式为##STR1##的四氢呋喃-3-醛的方法,其中R.sup.1是氢,或烷基或苯基基团,R.sup.2是烷基,(C.sub.1-C.sub.4-烷氧基)-羰基,(C.sub.1-C.sub.4-烷氧基)羰基亚甲基或苯基基团,或R.sup.1和R.sup.2一起是脂肪二基基团,包括在o-甲基苯甲酸的催化作用下,在大约100℃至250℃下加热式为##STR2##的4,5-二氢-1,3-二噁烷。优选每摩尔二噁烷使用约0.05至0.15摩尔o-甲基苯甲酸,并在大约120℃至200℃下在压力高达约10巴的条件下进行加热。这些化合物中有一些是具有杀虫和杀螨活性的新化合物。