PROCESSES FOR PREPARING ALPHA-NECRODYL COMPOUNDS AND PROCESSES FOR PREPARING GAMMA-NECRODYL COMPOUNDS
申请人:Shin-Etsu Chemical Co., Ltd.
公开号:US20220024847A1
公开(公告)日:2022-01-27
The present invention provides processes for preparing an α-necrodyl compound of the following general formula (3): wherein R
2
represents a monovalent hydrocarbon group having 1 to 9 carbon atoms, the process comprising: subjecting a 3, 5, 5-trimethyl-3-cyclopentene compound of the following general formula (1): wherein R
2
is as defined above, and X represents a leaving group, to a nucleophilic substitution reaction with a methylating agent of the following general formula (2): wherein M represents Li, MgZ
1
, ZnZ
1
, Cu, CuZ
1
, or CuLiZ
1
, and Z
1
represents a halogen atom or a methyl group, to form the α-necrodyl compound (3). The present invention further provides processes for preparing γ-necrodyl compounds of the following general formula (4): wherein R
2
represents a monovalent hydrocarbon group having 1 to 9 carbon atoms, the process comprising: subjecting the α-necrodyl compound (3) thus obtained to a positional isomerization reaction at the double bond to form the γ-necrodyl compound (4).
本发明提供了制备以下通式(3)的α-奈克罗酰基化合物的方法:其中R2代表具有1至9个碳原子的一价碳氢基团,该方法包括:将以下通式(1)的3,5,5-三甲基-3-环戊烯化合物进行亲核取代反应,其中R2如上所定义,X代表离去基团,使用以下通式(2)的甲基化试剂:其中M代表Li、MgZ1、ZnZ1、Cu、CuZ1或CuLiZ1,Z1代表卤素原子或甲基基团,以形成α-奈克罗酰基化合物(3)。本发明还提供了制备以下通式(4)的γ-奈克罗酰基化合物的方法:其中R2代表具有1至9个碳原子的一价碳氢基团,该方法包括:将得到的α-奈克罗酰基化合物(3)进行位置异构化反应,形成γ-奈克罗酰基化合物(4)。