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为氢,或烷基或苯基基团,R.sup.2为烷基,(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在一起为脂肪二亚基基团,包括在o-甲基苯甲酸催化下,在约100℃至250℃下加热式为##STR2## 的4,5-二氢-1,3-二氧杂环庚烷,优选每摩尔二氧杂环庚烷使用约0.05至0.15摩尔o-甲基苯甲酸,并在约120℃至200℃的温度下,在不超过10巴的压力下进行加热。这些化合物,其中一些是新的,具有杀虫和杀螨活性。