Process for preparing 2-oxindoles and n-hydroxy-2-oxindoles

    公开(公告)号:AU4767396A

    公开(公告)日:1996-08-21

    申请号:AU4767396

    申请日:1996-01-25

    Applicant: CATALYTICA INC

    Abstract: The present invention provides a processes, having practical utility, for preparing 2-oxindoles, N-hydroxy-2-oxindoles, or mixtures thereof comprising: catalytically hydrogenating a 2-nitroarylmalonate diester to produce a 2-(N-hydroxyamino)arylmalonate diester, a 2-aminoarylmalonate diester, or mixtures thereof as a first reaction intermediate; cyclizing, by intramolecular aminolysis of one ester group, the first reaction intermediate to produce a N-hydroxy-2-oxindole-3-carboxylate ester, 2-oxindole-3-carboxylate ester, or mixtures thereof as a second reaction intermediate; and hydrolyzing and decarboxylating the remaining ester group of the second reaction intermediate to produce the N-hydroxy-2-oxindole, the 2-oxindole, or mixtures thereof, wherein the cyclization reaction and the hydrolysis and decarboxylation reaction are conducted in situ with the catalytic hydrogenation reaction without isolation of said reaction intermediates.

    PROCESS FOR PREPARING 2-OXINDOLES AND N-HYDROXY-2-OXINDOLES

    公开(公告)号:CA2210695A1

    公开(公告)日:1996-08-08

    申请号:CA2210695

    申请日:1996-01-25

    Applicant: CATALYTICA INC

    Abstract: The present invention provides a processes, having practical utility, for preparing 2-oxindoles, N-hydroxy-2-oxindoles, or mixtures thereof comprising: catalytically hydrogenating a 2-nitroarylmalonate diester to produce a 2-(N-hydroxyamino)arylmalonate diester, a 2-aminoarylmalonate diester, or mixtures thereof as a first reaction intermediate; cyclizing, by intramolecular aminolysis of one ester group, the first reaction intermediate to produce a N-hydroxy-2-oxindole-3-carboxylate ester, 2-oxindole-3-carboxylate ester, or mixtures thereof as a second reaction intermediate; and hydrolyzing and decarboxylating the remaining ester group of the second reaction intermediate to produce the N-hydroxy-2-oxindole, the 2-oxindole, or mixtures thereof, wherein the cyclization reaction and the hydrolysis and decarboxylation reaction are conducted in situ with the catalytic hydrogenation reaction without isolation of said reaction intermediates.

    56.
    发明专利
    未知

    公开(公告)号:ES2084170T3

    公开(公告)日:1996-05-01

    申请号:ES91911705

    申请日:1991-06-12

    Applicant: CATALYTICA INC

    Abstract: This invention is a self-contained NOx sensor assembly. It may be used to detect NOx levels in a flowing gas stream such as might be found in an exhaust gas from a combustion process and to produce a measurable electrical output related to the content of NOx measured. The NOx sensor assembly is of a configuration that may be detached from a mounting and replaced. The sensor assembly comprises two sensor elements one of which is made up of a catalyst on a temperature measuring device. The other is a gas stream ambient temperature measuring device. The catalyst is selected and configured so that it selectively reduces NOx and the resulting heat of the reaction raises the temperature of the allied temperature measuring device. The sensor assembly also contains a NOx reductant source. The sensor assembly may be placed in a moving vehicle for measuring NOx levels in its exhaust gas.

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