Abstract: The transition-metal- and halogen-free synthesis of N-aryl substituted 1H-indazole and derivatives was accomplished on the basis of the iodobenzene-catalyzed intramolecular C -H amination of hydrazones under mild conditions. Reactions of hydrazones derived from ketones and hydrazines with a catalytic amount of iodobenzene in the presence of Oxone as an oxidant in trifluoroacetic acid took place to afford 1H indazoles in moderate to good yields.
Keywords: Hypervalent compounds, Amination, Cyclization, oxidant
[1]
N. A. S. Ali, B. A. Dar, V. Pradhan, M. Farooqui, Mini-Rev. Med. Chem. 2013, 13, 1792.
[2]
G. A. Bistocchi, G. D. Meo, M. Pedini, A. Ricci, H. Brouilhet, S. Boucherie, M. Rabaud, P. Jacquignon, Farmaco, Ed. Sci. 1981, 36, 315.
[3]
L. Mosti, L. Sansebastiano, P. Fossa, P. Schenone, F. Mattioli, Farmaco 1992, 47, 357.
[4]
D. A. Buthala, T. J. Lobl, Cytobios 1979, 25, 23.
[5]
For A Review, See: A. Schmidt, A. Beutler, B. Snovydovych, Eur. J. Org. Chem. 2008, 4073.
