Synthesis of Pentafluorinated β-Hydroxy Ketones

The LHMDS-promoted in situ generation of difluoroenolates from readily available 1-aryl and 1-alkyl 2,2,4,4,4-pentafluorobutan-1,3-dione hydrates has been used to produce a series of pentafluorinated beta-hydroxy ketones in up to 95% yield. The reaction proceeds under mild conditions, tolerates a wide range of functional groups, and is complete within 10 min. Reduction toward the corresponding 1,3-diol with DIBAL gives quantitative amounts and favors the formation of the syn-isomer.