Chemoselective and Regiospecific Formylation of 1-Phenyl-1H-pyrazoles Through the Duff Reaction

Abstract The synthesis of formylated 1-phenyl-1H-pyrazole derivatives under the Duff reaction conditions is reported. Our results indicate that 1-phenyl-1H-pyrazole systems containing electron-withdrawing and electron-donating substituents at the phenyl moiety react under the Duff reaction conditions to furnish formylated derivatives in good yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.