申请人:Montedison S.p.A.
公开号:US04673759A1
公开(公告)日:1987-06-16
A process for the preparation of 2-alkyl cyclopent-2-enones having the formula: ##STR1## wherein R is as defined hereinafter. An .alpha.-olefin having the formula CH.sub.2 .dbd.CH--CH.sub.2 R is oxidized to the corresponding epoxide. The epoxide is reacted with an alkylating agent having the formula Na.sup.+ [CH(COOR").sub.2 ].sup.-, wherein R" is an ethyl, an isopropyl, or an isobutyl radical. An .alpha.-carbalkoxy-.gamma.-alkyl lactone is obtained, which, through saponification and decarboxylation, yields a .gamma.-alkyl lactone having the formula: ##STR2## which is reacted with a protic acid, thereby obtaining, by cyclization, the desired 2-alkylcyclopent-2-enone. The obtained products are intermediates for the production of pharmaceutical products and of drugs for veterinary use, in particular prostaglandin.
制备具有以下式子的2-烷基环戊-2-烯酮的方法:##STR1## 其中R的定义在下文中。将具有以下式子的α-烯烃CH.sub.2.dbd.CH-CH.sub.2R氧化为对应的环氧化物。将环氧化物与具有以下式子的烷基化试剂Na.sup.+ [CH(COOR").sub.2].sup.-反应,其中R"是乙基、异丙基或异丁基基团。得到α-羧酸酯-γ-烷基内酯,通过皂化和脱羧反应,得到具有以下式子的γ-烷基内酯:##STR2## 通过与质子酸反应,通过环化反应得到所需的2-烷基环戊-2-烯酮。所得产品是制备药物和兽医用药物的中间体,特别是前列腺素。