Global Patent Index - EP 0946533 A1

EP 0946533 A1 19991006 - PROCESS FOR PREPARING 2,1,3-BENZOTHIADIAZOLES

Title (en)

PROCESS FOR PREPARING 2,1,3-BENZOTHIADIAZOLES

Title (de)

VERFAHREN ZUR HERSTELLUNG VON 2,1,3-BENZOTHIADIAZOLEN

Title (fr)

PROCEDE DE PREPARATION DE 2,1,3-BENTHIADIAZOLES

Publication

EP 0946533 A1 19991006 (DE)

Application

EP 97952031 A 19971203

Priority

  • DE 19652222 A 19961216
  • EP 9706752 W 19971203

Abstract (en)

[origin: DE19652222A1] The invention concerns an improved process for preparing 2,1,3-benzothiadiazoles of general formula (I), in which the groups R<1>, R<2>, R<3> and R<4> can be identical or different and designate a hydrogen group or a hydrocarbon atom with between 1 and 4 carbon atoms, by reacting o-phenylene diamines of general formula (II), in which the groups R<1>, R<2>, R<3> and R<4> have the above meanings, with sulphur dioxide. The process is characterized in that gaseous sulphur dioxide is mixed into the o-phenylene diamine to be reacted in the liquid phase in the absence of an additional solvent and in the absence of a catalyst at reaction temperatures of between 50 and 100 DEG C and a pressure of between 0.9 and 1.5 bar.

IPC 1-7

C07D 285/14

IPC 8 full level

C07D 285/14 (2006.01)

CPC (source: EP)

C07D 285/14 (2013.01)

Citation (search report)

See references of WO 9827076A1

Designated contracting state (EPC)

DE FR GB IT

DOCDB simple family (publication)

DE 19652222 A1 19980618; AU 5559998 A 19980715; EP 0946533 A1 19991006; WO 9827076 A1 19980625

DOCDB simple family (application)

DE 19652222 A 19961216; AU 5559998 A 19971203; EP 9706752 W 19971203; EP 97952031 A 19971203