4.
    发明专利
    未知

    公开(公告)号:DE19858360A1

    公开(公告)日:2000-06-21

    申请号:DE19858360

    申请日:1998-12-17

    Applicant: BASF AG

    Abstract: In the preparation of 2,4-dimethyl-pyrrole (I) by hydrolysis of 2,4-dimethyl-3,5-bis-alkoxycarbonyl-pyrrole (II) to the dicarboxylic acid (III) with strong alkali and thermal decarboxylation of (III), (II) is heated under reflux with 10-30% aqueous alkali hydroxide, and then neutralized with acid. Heating under reflux is continued to complete decarboxylation.

    5.
    发明专利
    未知

    公开(公告)号:DE19858352A1

    公开(公告)日:2000-06-21

    申请号:DE19858352

    申请日:1998-12-17

    Applicant: BASF AG

    Abstract: In the preparation of 2,4-dimethyl-3,5-bis-alkoxycarbonyl-pyrroles (I) by nitrosing an alkyl acetoacetate (II) to the alkyl 2-nitrosoacetoacetate (III), reducing (III) to the amine (IV) and ring-closing condensation with unsubstituted (II), (III) is hydrogenated with hydrogen in the presence of a noble metal catalyst and condensed with (II) without isolating (IV).

    7.
    发明专利
    未知

    公开(公告)号:DE19856376A1

    公开(公告)日:2000-06-08

    申请号:DE19856376

    申请日:1998-12-07

    Applicant: BASF AG

    Abstract: The invention relates to methods for producing or purifying onium hydroxides of elements N, S or P by means of electrodialysis in an electrodialysis device comprising one or several cell units. Each cell unit consists of a bipolar membrane and an anionically selective membrane and a bipolar membrane or a cationically selective membrane is arranged between the last anionically selective membrane and the anode.

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