PROCESS FOR PRODUCING INTERMEDIERS OF CEPH-3-EME-4-CARBOXYLIC ACIDS
摘要
A process is disclosed for the preparation of a compound of the formula <IMAGE> I where R and R1 are defined herein below, wherein a compound of the structure; <IMAGE> II is reacted in a suitable solvent with a haloamide in the presence of a metal oxide or a haloamide in the presence of a free radical initiator under the influence of light or heat or alternatively with a halogen in the presence of a metal oxide, to give a compound of the structure; <IMAGE> III which compound, in a suitable solvent is reacted with a suitable nucleophilic reagent to obtain the compound; <IMAGE> IV which compound is then subjected to allylic halogenation to give a compound of the structure; <IMAGE> V which is then reacted with a reducing agent to yield I.
