Triacetoxyperiodinane → HCID 118023953, compound

Participants

Reaction Conditions

Reaction Steps

N-(3-chloro-1-(pyridin-3-yl)-1H-pyrazol-4-yl)-N-ethyl-2-methyl-4-oxobutanamide (0.390 g, 1.22 mmol) was dissolved in THF (12 mL) at −78° C. To this stirring solution was added dropwise methylmagnesium bromide (0.446 mL, 1.34 mmol). The reaction mixture was stirred at −78° C. for 30 minutes and was warmed to 0° C., at which point the reaction was quenched with a saturated aqueous NH4Cl solution. The reaction product was extracted with diethyl ether, and the combined organics were washed with brine, then dried over Na2SO4 and concentrated under vacuum to provide a yellow oil. The oil was loaded onto CELITE® and purified by flash column chromatography using 0-50% acetone/hexanes as eluent. The secondary alcohol recovered as an impure oil was used immediately. The residual oil was taken up in CH2Cl2 (10 mL) and buffered with NaHCO3 (0.153 g, 1.82 mmol). The resulting mixture was cooled to 0° C. and Dess-Martin periodinane (0.516 g, 1.22 mmol) was added in a single portion. The reaction mixture was stirred at 0° C. for 1 hour, then was warmed to room temperature. The reaction was quenched by slow addition of a saturated aqueous sodium bisulfite solution, and extracted with CH2Cl2. The organic layer was washed with brine, dried over Na2SO4 and concentrated to an oil that was loaded directly onto CELITE®. Purification by flash column chromatography using 0-40% acetone/hexanes as eluent provided the title compound as a clear, colorless oil. (0.0900 g, 20% over two steps).

Provenance & Evidence