6533b85dfe1ef96bd12bded4

RESEARCH PRODUCT

Synthesis of Fluorinated Indazoles Through ANRORC-Like Rearrangement of 1,2,4-Oxadiazoles with Hydrazine.

Andrea PaceSilvestre BuscemiNicolò VivonaIvana PibiriAntonio Palumbo-piccionello

subject

IndazoleDenticityOrganic ChemistryHydrazine124-oxadiazoleGeneral MedicineRing (chemistry)BiochemistryMedicinal chemistrychemistry.chemical_compoundchemistryNucleophileNucleophilic aromatic substitutionYield (chemistry)Drug DiscoveryElectrophileindazoleOrganic chemistryfluorinated heterocycleANRORC-like rearrangements

description

A series of 6-substituted fluorinated indazoles has been obtained through an ANRORC-like rearrangement (Addition of Nucleophile, Ring-Opening and Ring-Closure) of 5-tetrafluorophenyl-1,2,4-oxadiazoles with hydrazine. The initial addition of the bidentate nucleophile to the electrophilic C(5) of the 1,2,4-oxadiazole ring, followed by ring opening and ring closure, leads to the formation of fluorinated indazoles in high yield under mild experimental conditions. Functionalization of the C(6) in the final indazole nucleus was preliminarily achieved through a nucleophilic aromatic substitution on the starting 5-pentafluorophenyl-1,2,4-oxadiazole.

https://doi.org/10.1002/chin.200652127