[EN] PREPARATION OF 6-SUBSTITUTED MENADIONES [FR] PRÉPARATION DE MÉNADIONES 6-SUBSTITUÉES
摘要:
The present invention relates to a process for the preparation of a compound having formula (I) wherein R is selected from the group consisting of: halogen, (C1-C6)alkoxy, (C1-C6)alkyl, halo(C1-C6)alkyl, and halo(C1-C6)alkoxy, said process comprising a step of intramolecular cyclisation, a step of bromination, a step of aromatization and a step of oxidation.
Herein, we report a safe and economical multigramsynthesis of 6-fluoromenadione, an intermediate in the synthesis of novel biologically active agents. The key to this six-step sequence process involves the condensation of the readily available starting 4′-fluoropropiophenone and glyoxylic acid, a bromination–elimination sequence from 7-fluoro-3-methyltetral-1-one allowing aromatization of the naphthol