PROCESS FOR THE PREPARATION OF 5-FLUORO-1H-PYRAZOLES

摘要

A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I);is described, resulting from the reaction of an olefin of the general formula (II);with hydrazines of the formula (III);R1—NH—NH2   (III),whereinR1 is selected from C1-C6 alkyl, C5-C10 aryl;R2 is a trihalomethyl moiety with at least one fluorine atom; andR3 is selected from C1-C5 haloalkyl, CF3, C2F5, C3F7, CF2CF2Cl, CFClCF3,in the presence of water and a base.

主权项

1. Process for synthesis of 5-fluoro-1H-pyrazole of formula (I) comprising reacting an olefin of formula (II) with a hydrazine of formula (III)
R1−NH−NH2   (III), wherein R1 is selected from C1-C6 alkyl, C5-C10 aryl; R2 is a trihalomethyl moiety with at least one fluorine atom; and R3 is selected from C1-C5 haloalkyl, in the presence of water and a base.