posted on 2020-09-01, 13:08authored byRana Alsalim, Peter Lindemann, María Pascual López-Alberca, Sandra Miksche, Werngard Czechtizky, Nis Halland, Marc Nazaré
The development of
a novel selective synthesis of 3-amino-2H-indazoles
from readily available 2-halobenzonitriles is
presented. The reaction proceeds through a domino reaction sequence,
consisting of a regioselective palladium-catalyzed coupling of monosubstituted
hydrazines with 2-halobenzonitriles, followed by an intramolecular
hydroamination through a 5-exo-dig cyclization and subsequent isomerization
to directly afford a wide variety of substituted 2H-indazole analogues in good to excellent yields.