PROCESS FOR PREPARING DIFLUOROMETHYLPYRAZOLYL CARBOXYLATES

• Main Authors: DIETZ JOCHEN, ZIERKE THOMAS, SMIDT SEBASTIAN PEER, GROTE THOMAS, SUKOPP MARTIN, RHEINHEIMER JOACHIM, RACK MICHAEL, LOHMANN JAN KLAAS, KEIL MICHAEL, LOEHR SANDRA
• Format: Patent
• Language: English; Korean
• Published: 23.07.2009
• Subjects: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAININGELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN,SULFUR, SELENIUM OR TELLURIUM; CHEMISTRY; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY

The present invention relates to a process for preparing difluoromethyl-substituted pyrazol-4-yl carboxylates of the formula (I) in which R1 is C1-C8-alkyl, C3-C8-cycloalkyl, C1-C4-alkoxy-C1-C4-alkyl, etc.; and R2 is hydrogen, C1-C4-alkyl, benzyl or phenyl, wherein a) a compound of the general formula (II) in which X is fluorine, chlorine, or bromine, R1 has one of the definitions given above, and R4 is C1-C8-alkyl, C3-C8-cycloalkyl, C2-C8-alkenyl, benzyl or phenyl, is reacted with a silane compound of the general formula R3nSiCl(4-n) in which n is 1, 2 or 3 and the substituents R3 are each independently selected from C1-C8-alkyl and phenyl, and with a metal which is selected from the metals of groups 1, 2, 3, 4 and 12 of the periodic table and has a redox potential of less than-0.7 V, based on a standard hydrogen electrode (at 25°C and 101.325 kPa); and b) the reaction mixture from step a) is reacted with a compound of the general formula (III) in which R2 has one of the definitions given above.