One-Pot (3 + 2) Cycloaddition–Isomerization–Oxidation of 2,2,2-Trifluorodiazoethane and Styryl Derivatives
Julia Altarejos, Estíbaliz Merino, David Sucunza, Juan J. Vaquero, and Javier Carreras*
J. Org. Chem. 2023, ASAP
DOI: 10.1021/acs.joc.3c00396
A facile access to 5-aryl-3-trifluoromethylpyrazoles has been developed by a one-pot (3 + 2) cycloaddition–isomerization–oxidation sequence employing 2,2,2-trifluorodiazoethane and styryl derivatives. A broad variety of functional groups and good yields are achieved under mild conditions. Additionally, the functionalization of 3-trifluoromethylpyrazoles was studied. DFT calculations of the cycloaddition transition state energies are consistent with the experimentally observed reactivity. |