Process for the preparation of 6-hydroxy chromans
    2.
    发明授权
    Process for the preparation of 6-hydroxy chromans 失效
    制备6-羟基染料的方法

    公开(公告)号:US3801603A

    公开(公告)日:1974-04-02

    申请号:US3801603D

    申请日:1972-01-06

    Applicant: BAYER AG

    Inventor: HARTMANN P ROOS E

    CPC classification number: C07D311/58

    Abstract: 6-HYDROXY CHROMANS ARE PREPARED BY REACTING A HYDROQUINONE WITH A 1,3-DIENE IN A TWO-PHASE AQUEOUS MINERAL ACID/HYDROCARBON SOLVENT SYSTEM AT AN ELEVATED TEMPERATURE, CONTINUOUSLY REMOVING A PORTION OF THE ORGANIC SOLVENT PHASE DURING THE REACTION, EVAPORATING SOLVENT CONTAINED THEREIN AND RETURNING SAME TO THE REACTION MIXTURE, AND ISOLATING THE 6-HYDROXY CHROMAN FORMED.

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