Transformation of carboxylic acid esters into 2-substituted allyl halides through tertiary cyclopropyl sulfonates. Application in the synthesis of (±)-ipsenol and (±)-ipsdienol, components of Ips typographus spark beetle pheromone
摘要:
Cyclopropanation of the ester group in ethyl 3-chloropropanoate and subsequent cleavage of the three-membered carbocycle in intermediate 1-(2-chloroethyl)cyclopropyl methanesulfonate gave 2-bromomethyl-4-chlorobut-1-ene, and the latter was used as key intermediate in the synthesis of racemic ipsenol and ipsdienol which are components of Ips typographus L. European spruce spark beetle pheromone.
The present invention relates to a process for the preparation of cis-2-(2-methylprop-1-enyl)-4-methyltetrahydropyran comprising the catalytic hydrogenation of 2-(2-methylprop-1-enyl)-4-methylenetetrahydropyran in the presence of hydrogen and a heterogeneous catalyst comprising ruthenium on a support and subsequently bringing the compounds obtained in this way into contact with a strongly acidic cation exchanger.
The present invention relates to a process for the preparation of a composition enriched in cis-2-(2-methylprop-1-enyl)-4-methyltetrahydropyran, comprising the catalytic hydrogenation of 2-(2-methylprop-1-enyl)-4-methylenetetrahydropyran in the presence of hydrogen and a heterogeneous catalyst comprising ruthenium.
[EN] METHOD FOR PRODUCING DEHYDRO ROSE OXIDE<br/>[FR] PROCÉDÉ DE PRODUCTION D'OXYDE DE ROSE DÉSHYDRO
申请人:BASF SE
公开号:WO2014184311A1
公开(公告)日:2014-11-20
The present invention relates to a method for producing dehydro rose oxide by reacting isoprenol and prenal in the presence of at least one sulfonic acid of formula R1-SO3H as catalyst, wherein R1 is selected from phenyl which carries 2 or 3 C1-C4-alkyl substituents, phenyl which carries one C8-C20-alkyl substituent and optionally also 1 or 2 C1-C4-alkyl substituents, and naphthyl which optionally carries 1 or 2 C1-C4-alkyl substituents.
The use as fragrance ingredient of 4—methylene—2—(2—methylprop—1—enyl)—tetrahydropyran.
4-亚甲基-2-(2-甲基丙烯基)-四氢吡喃作为香料成分的用途。
PRODUCTION OF 2-SUBSTITUTED 4-METHYL-TETRAHYDROPYRANS FROM STARTING MATERIALS CONTAINING 2-ALKYL-4,4-DIMETHYL-1,3-DIOXANES
申请人:BASF SE
公开号:US20170037020A1
公开(公告)日:2017-02-09
The invention relates to a method for producing 2-substituted 4-methyltetrahydropyrans of general formula (I) from starting materials containing at least one 2-substituted 4,4-dimethyl-1,3-dioxane of general formula (II).