EP 0843665 A1 19980527 - METHOD OF PREPARING 1,2-DIMETHYL-3,5-DIARYLPYRAZOLIUM METHYLSULPHATES
Title (en)
METHOD OF PREPARING 1,2-DIMETHYL-3,5-DIARYLPYRAZOLIUM METHYLSULPHATES
Title (de)
VERFAHREN ZUR HERSTELLUNG VON 1,2-DIMETHYL-3,5-DIARYL-PYRAZOLIUM-METHYLSULFATEN
Title (fr)
PROCEDE DE PREPARATION DE 1,2-DIMETHYL-3,5-DIARYLPYRAZOLIUMMETHYLSULFATES
Publication
Application
Priority
- DE 19529056 A 19950808
- EP 9603316 W 19960726
Abstract (en)
[origin: DE19529056A1] The invention concerns a method of preparing 1,2-dimethyl-3,5-diarylpyrazolium methylsulphates of general formula (I) in which R<1> and R<2>, independently of each other, may be hydrogen, C1-C4 alkyl, C3-C8 cycloalkyl, C1-C4 alkoxy, halogen, nitro C1-C4 haloalkyl, aryl or other substituents which are inert under the conditions of the reaction. The method calls for 1-methyl-3,5-diarylpyrazoles of general formula (II), in which R<1> and R<2> are as defined above, to be reacted at elevated temperatures with a) methanol and SO3, b) methanol and sulphuric acid and/or c) methanol and methylsulphuric acid.
IPC 1-7
IPC 8 full level
C07D 231/12 (2006.01)
CPC (source: EP US)
C07D 231/12 (2013.01 - EP US)
Citation (search report)
See references of WO 9706148A1
Designated contracting state (EPC)
AT BE CH DE ES FR GB IT LI NL
DOCDB simple family (publication)
DE 19529056 A1 19970213; AU 6738096 A 19970305; AU 702286 B2 19990218; CA 2223973 A1 19970220; CN 1092186 C 20021009; CN 1192734 A 19980909; EP 0843665 A1 19980527; JP H11510503 A 19990914; US 5847154 A 19981208; WO 9706148 A1 19970220
DOCDB simple family (application)
DE 19529056 A 19950808; AU 6738096 A 19960726; CA 2223973 A 19960726; CN 96196116 A 19960726; EP 9603316 W 19960726; EP 96927616 A 19960726; JP 50808197 A 19960726; US 98192598 A 19980113