Patents by Inventor Michelle L. Chang

Michelle L. Chang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5637765
    Abstract: A process for the preparation of 2-chloro-4,5-difluorobenzoic acid and 2,4,5-trifluorobenzoic acid as well as synthetic intermediates useful in and prepared according thereto, comprising reacting a nitrobenzene having the formula ##STR1## wherein X is chloro or fluoro, with an appropriate carbanion to form a compound having the formula ##STR2## wherein one of Y and Z is chloro and the other is nitro, and R is a radical selected from the group consisting of --CCl.sub.3, --CH.sub.2 NO.sub.2, --CH(NO.sub.2)R.sup.1, --CH(CO.sub.2 R.sup.1).sub.2, --CH(C(O)R.sup.2).sub.2, --CH(CN)CO.sub.2 R.sup.1, --CH(CO.sub.2 R.sup.1)COR.sup.2 and --COR.sup.2 where R.sup.1 is alkyl or arylalkyl and R.sup.2 is alkyl, aryl or arylalkyl and, where appearing more than once in such a radical, R.sup.1 and R.sup.2 may be the same or different at each occurrence.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: June 10, 1997
    Assignee: Abbott Laboratories
    Inventors: Xiu C. Wang, Panos Kalaritis, Michelle L. Chang
  • Patent number: 5633399
    Abstract: A process for the preparation of 2-chloro-4,5-difluorobenzoic acid and 2,4,5-trifluorobenzoic acid as well as synthetic intermediates useful in and prepared according thereto, comprising reacting a nitrobenzene having the formula ##STR1## wherein X is chloro or fluoro, with an appropriate carbanion to form a compound having the formula ##STR2## wherein one of Y and Z is chloro and the other is nitro, and R is a radical selected from the group consisting of --CCl.sub.3, --CH.sub.2 NO.sub.2, --CH(NO.sub.2)R.sup.1, --CH(CO.sub.2 R.sup.1).sub.2, --CH(C(O)R.sup.2).sub.2, --CH(CN)CO.sub.2 R.sup.1, --CH(CO.sub.2 R.sup.1)COR.sup.2 and --COR.sup.2 where R.sup.1 is alkyl or arylalkyl and R.sup.2 is alkyl, aryl or arylalkyl and, where appearing more than once in such a radical, R.sup.1 and R.sup.2 may be the same or different at each occurrence.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: May 27, 1997
    Assignee: Abbott Laboratories
    Inventors: Xiu C. Wang, Panos Kalaritis, Michelle L. Chang
  • Patent number: 5576455
    Abstract: A process for the preparation of 2-chloro-4,5-difluorobenzoic acid and 2,4,5-trifluorobenzoic acid as well as synthetic intermediates useful in and prepared according thereto, comprising reacting a nitrobenzene having the formula ##STR1## wherein X is chloro or fluoro, with an appropriate carbanion to form a compound having the formula ##STR2## wherein one of Y and Z is chloro and the other is nitro, and R is a radical selected from the group consisting of --CCl.sub.3, --CH.sub.2 NO.sub.2, --CH(NO.sub.2)R.sup.1, --CH(CO.sub.2 R.sup.1).sub.2, --CH(C(O)R.sup.2).sub.2, --CH(CN)CO.sub.2 R.sup.1, --CH(CO.sub.2 R.sup.1)COR.sup.2 and --COR.sup.2 where R.sup.1 is alkyl or arylalkyl and R.sup.2 is alkyl, aryl or arylalkyl and, where appearing more than once in such a radical, R.sup.1 and R.sup.2 may be the same or different at each occurrence.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: November 19, 1996
    Assignee: Abbott Laboratories
    Inventors: Xiu C. Wang, Panos Kalaritis, Michelle L. Chang
  • Patent number: 5294721
    Abstract: A process for the preparation of halobenzoic acids, comprising the step of reacting a halonitrobenzene with a pyridinium salt to form an intermediate of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, alkyl, aryl, alkenyl, alkynyl, --CN, --COOR' and --COR' where R' is alkyl or aryl; X is chloro or fluoro; Y is hydrogen, chloro or fluoro; and Z is chloro, bromo or iodo.
    Type: Grant
    Filed: August 21, 1992
    Date of Patent: March 15, 1994
    Assignee: Abbott Laboratories
    Inventors: Xiu C. Wang, Panos Kalaritis, Michelle L. Chang