申请人:Dynamit Nobel AG
公开号:US04673760A1
公开(公告)日:1987-06-16
Disclosed is a process for preparing cis-trans isomer mixtures of 2,2-dimethyl-3(.beta.,.beta.-dichlorovinyl)-cyclopropane-1-carboxylic acid esters, having a high cis/trans isomer ratio, wherein a 4,4-dimethyl-5-halogen-6-alkoxytetrahydro-pyrone or a 3,3-dimethyl-4-halogen-5-oxo-pentanic acid ester is reacted with dichlorophosphonic acid esters in the presence of alkali alcoholates or alkali hydrides or lithium alkyls. Also disclosed are novel starting tetrahydropyrone compounds usable in the above process, and a process for preparation of the novel compounds which includes reacting .beta.,.beta.-dimethyl-.gamma.,.delta.-dihalogen-.delta.-valerolactones with alkali alcoholates at reaction temperatures between -10.degree. and +50.degree. C.
揭示了一种制备2,2-二甲基-3(β,β-二氯乙烯基)-环丙烷-1-羧酸酯的顺-反异构体混合物的过程,其具有高顺/反异构体比例,其中4,4-二甲基-5-卤代-6-烷氧基四氢吡喃或3,3-二甲基-4-卤代-5-氧代戊酸酯在碱性醇酸酯或碱性氢化物或锂烷基的存在下与二氯膦酸酯反应。还揭示了在上述过程中可用的新型起始四氢吡喃化合物,以及一种制备这些新型化合物的过程,其中包括将β,β-二甲基-γ,δ-二卤代-δ-戊内酯与碱性醇酸酯在-10℃至+50℃的反应温度下反应。