申请人:SCM Corporation
公开号:US04293497A1
公开(公告)日:1981-10-06
Disclosed is a process for the coupling of a Grignard reagent RMgX with an allylic halide in the presence of a dipolar aprotic solvent wherein the improvement, for obtaining improved yield and selectivity, comprises adding a catalyst to said Grignard or allylic halide and then carrying out the coupling reaction by the addition on the Grignard reagent to the allylic halide, said reaction being characterized by the displacement at the gamma position (relative to the halide) of the allylic halide with R of the Grignard reagent, migration of the allylic double bond in the direction of the halogen atom and loss of halogen. The present invention also resides in the discovery of certain novel procedures for the synthesis of Vitamin E. Specific embodiments of this aspect of the invention reside in the syntheses of 6,7-dehydrophytol, 10,11-dihydrofarnesene, phytone, hexahydropseudoionone, and related compounds as precursors for Vitamin E.
本发明公开了一种在二极性无质子溶剂存在下,将Grignard试剂RMgX与烯丙基卤化物偶联的方法,其中改进在于为了获得更好的产率和选择性,向所述Grignard试剂或烯丙基卤化物中添加催化剂,然后通过向烯丙基卤化物中加入Grignard试剂进行偶联反应,所述反应的特征在于通过Grignard试剂的R取代烯丙基卤化物的γ位(相对于卤化物),使烯丙基双键向卤素原子方向迁移并失去卤素。本发明还涉及发现某些合成维生素E的新程序。本发明的特定实施例涉及合成6,7-去氢叶酸、10,11-二氢法尼烯、萜烯酮、六氢假离子酮和相关化合物,作为维生素E的前体。