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2-Aryl-6-Polyfluoroalkyl-4-Pyrones as Promising R^F-Building-Blocks: Synthesis and Application for Construction of Fluorinated Azaheterocycles.

ABSTRACT: A convenient and general method for the direct synthesis of 2-aryl-6-(trifluoromethyl)-4-pyrones and 2-aryl-5-bromo-6-(trifluoromethyl)-4-pyrones has been developed on the basis of one-pot oxidative cyclization of (E)-6-aryl-1,1,1-trifluorohex-5-ene-2,4-diones via a bromination/dehydrobromination approach. This strategy was also applied for the preparation of 2-phenyl-6-polyfluoroalkyl-4-pyrones and their 5-bromo derivatives. Conditions of chemoselective enediones bromination were found and the key intermediates of the cyclization of bromo-derivatives to 4-pyrones were characterized. Synthetic application of the prepared 4-pyrones has been demonstrated for the construction of biologically important CF₃-bearing azaheterocycles, such as pyrazoles, pyridones, and triazoles.

SUBMITTER: Usachev SA

PROVIDER: S-EPMC8347980 | biostudies-literature |

REPOSITORIES: biostudies-literature

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