Direct Formation of 2-Substituted 2H-Indazoles by a Pd-Catalyzed Reaction between 2-Halobenzyl Halides and Arylhydrazines.
J Org Chem
; 86(2): 1408-1418, 2021 01 15.
Article
en En
| MEDLINE
| ID: mdl-33306383
ABSTRACT
A direct and operationally simple method for the regioselective synthesis of 2-aryl-substituted 2H-indazoles is reported. The Pd-catalyzed reaction between easily available 2-bromobenzyl bromides and arylhydrazines employing Cs2CO3 as the base and t-Bu3PHBF4 as the ligand in DMSO at 120 °C in a sealed tube delivers the 2-substituted-2H-indazoles in a single synthetic step with yields up to 79%. The new method is based on a regioselective intermolecular N-benzylation followed by intramolecular N-arylation and oxidation.
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MEDLINE
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En
Revista:
J Org Chem
Año:
2021
Tipo del documento:
Article
País de afiliación:
Jordania