PROCESS FOR THE PREPARATION OF FIPRONIL, AN INSECTICIDE, AND RELATED PYRAZOLES

PROCESS FOR THE PREPARATION OF FIPRONIL, AN INSECTICIDE, AND RELATED PYRAZOLES

This invention relates to a process for the preparation of 5-amino-1-phenyl-3-cyano-4-trifluoromethyl sulphinyl pyrazoles as defined by Formula-I, wherein: R1=trifluoromethyl or trifluoromethoxy, and R2, R3=individually hydrogen, chlorine or bromine, the process comprising the step of oxidizing a co...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: MALTE, ASHOKKUMAR, MAGANLAL, SATHE, SHEKHAR, VISHWANATH, JOSEPH, PULINATTU, CHERIAN, DAMANIA, PRAGNESH, DALPATRAM, PARKAR, SURESHKUMAR, DATTATRAYA, GHARDA, KEKI, HORMUSJI
Format: Patent
Sprache:eng ; fre ; ger
Schlagworte:
CHEMISTRY
HETEROCYCLIC COMPOUNDS
METALLURGY
ORGANIC CHEMISTRY
Online-Zugang:Volltext bestellen
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:This invention relates to a process for the preparation of 5-amino-1-phenyl-3-cyano-4-trifluoromethyl sulphinyl pyrazoles as defined by Formula-I, wherein: R1=trifluoromethyl or trifluoromethoxy, and R2, R3=individually hydrogen, chlorine or bromine, the process comprising the step of oxidizing a compound of Formula-II, wherein: R1=trifluoromethyl or trifluoromethoxy, and R2, R3=individually hydrogen, chlorine or bromine, in a medium comprising at least one oxidizing agent and trichloro acetic acid, and/or the reactions product (s) of the at least one oxidizing agent and trichloro acetic acid, and at least one melting point depressant. The preferred pyrazole is Fipronil, preferably prepared using hydrogen peroxide and dichloro acetic acid at room temperature.