The process according to the present invention can produce the ketolactones (3), important intermediates for the symthesis of 20-ethyl-prostanglandins, in remarkably improved yields and for a shortened period of time by reactiong the Corey aldehydes (2) with di-lower-alkyl (2-oxononyl)phosphates in halogenated hydrocarbons under the presence of lithium halides and tertiary amines, whereby said Corey aldehydes (2) are prepared through DMSO oxidation of the Corey lactones (1) in halogenated hydrocarbons.
根据本发明的工艺可以生产酮内酯 (3),这是合成 20-乙基-丙甾烷的重要中间体、在卤化
锂和叔胺存在下,科里醛(2)与二低级烷基(2-氧代壬基)
磷酸盐在卤代烃中反应,可显著提高产率并缩短反应时间,其中所述科里醛(2)是通过
科里内酯(1)在卤代烃中的
DMSO 氧化反应制备的。