公开(公告)号：AU1706792A

公开(公告)日：1992-11-26

申请号：AU1706792

申请日：1992-05-21

Applicant: HOECHST AG

Inventor： THEODOR PAPENFUHS ,  RALF PFIRMANN

IPC: C07C51/083 ,  C07C51/377 ,  C07C51/56 ,  C07C51/567 ,  C07C63/68 ,  C07D307/89

Abstract: Process for the preparation of 3,4,6-tetrafluorophthalic acid of the formula (1) (1) or the anhydride thereof in good yields and in an advantageous manner, by dehalogenating tetrafluorophthalic anhydride of the formula (2) (2) or tetrafluorophthalic acid in aqueous-alkaline medium using zinc at temperatures of approximately 20 DEG C. to approximately 160 DEG C. and, if appropriate, converting the resulting 3,4,6-trifluorophthalic acid into the anhydride in a known manner by dehydrating it.

公开(公告)号：ZA9201040B

公开(公告)日：1992-10-28

申请号：ZA9201040

申请日：1992-02-13

Applicant: HOECHST AG

Inventor： FOLZ GEORG ,  GEORG FOLZ ,  PAPENFUHS THEODOR ,  THEODOR PAPENFUHS

IPC: B01J27/128 ,  C07B61/00 ,  C07C303/22 ,  C07C313/04 ,  C07C315/00 ,  C07C317/14 ,  C07C

CPC classification number: C07C313/04 ,  C07C303/22 ,  C07C315/00 ,  C07C317/14 ,  C07C309/86

公开(公告)号：ZA921040B

公开(公告)日：1992-10-28

申请号：ZA921040

申请日：1992-02-13

Applicant: HOECHST AG

Inventor： FOLZ GEORG ,  GEORG FOLZ ,  PAPENFUHS THEODOR ,  THEODOR PAPENFUHS

IPC: C07B61/00 ,  B01J27/128 ,  C07C303/22 ,  C07C313/04 ,  C07C315/00 ,  C07C317/14 ,  C07C

Abstract: Process for the preparation of 4-alkylsulfonyl-1-alkyl-2-chlorobenzenes and like compounds.A process for the preparation of 4-alkyl(C1-C4)-sulfonyl-1-alkyl-2-chlorobenzenes, in very good yields and with high selectivity by selectively chlorinating a p-alkyl-benzenesulfonyl chloride with gaseous chlorine in the presence of a chlorine carrier at 50° C. to 100° C. to give a compound of the formulain which R1 is an alkyl (C1-C4) group, subsequently reducing the latter in an aqueous medium at a pH of 8 to 10 with sodium hydrogen sulfite or sodium sulfite at 40 to 90° C. to give a compound of the formulaand reacting the latter with alkyl(C1-C4) chloride in the presence of an acid binder at 80 to 150° C., and also compounds of the last mentioned formula which, instead of the -SO2Na group contain the -SO2X group (X=hydrogen atom or alkali metal atom).