ChemInform Abstract: FLUOROALKYL‐CONTAINING MONO‐ AND BISPYRAZOLES

Abstract

Die Hydrazine (II) reagieren mit den fluorhaltigen β‐Diketonen (I) bzw. Bis‐β‐diketonen (IV) zu den Pyrazolen (III) bzw. Bispyrazolen (V).

Fluoroalkyl Amino Reagents (FARs): A General Approach towards the Synthesis of Heterocyclic Compounds Bearing Emergent Fluorinated Substituents

“…Previous work already described the synthesis of pyrazoles bearing two fluorinated groups by reaction of bisperfluoroalkyl diketones with hydrazines, but the synthesis, isolation and purification of the starting fluorinated diketones is very complex [ 85 , 86 , 87 , 88 , 89 , 90 ]. To circumvent these issues, FARs proved a very valuable tool and allowed to develop a scalable and operationally convenient method.…”

A General Approach towards NH‐Pyr­azoles That Bear Diverse Fluoroalkyl Groups by Means of Fluorinated Iminium Salts

“…[35][36][37][38][39][40][41] For example 3,5-bis(fluoroalkyl)pyrazoles are prepared by reacting bisperfluoroalkyl β-diketones with hydrazines in yields of only 27-40 %. [38] Moreover, the synthesis, isolation and purification of polyfluoroalkyl diketones are troublesome because the compounds are generally very volatile, easily form hydrates, and are sometimes highly toxic. We reported recently on the synthesis of 3,5-bis-(fluoroalkyl)pyrazoles by starting from fluoroacetoacetates.…”