m-Chloroperbenzoic acid → 3-{[5-(Methylsulfinyl)-1,3-thiazol-2-yl]carbamoyl}phenyl acetate

Beteiligte Stoffe

Reaktionsschritte

A solution of m-chloroperbenzoic acid (0.458 g, 2.04 mmol, maximum 77%) is dissolved in dichloromethane (8.0 mL) and added dropwise over 15 minutes to a solution of 516 (0.630 g, 2.04 mmol) dissolved in dichloromethane (25.0 mL). The reaction is stirred at room temperature for 6 hours. The reaction is then partitioned between dichloromethane and saturated aqueous sodium thiosulfate. The organic layer is washed again with a saturated aqueous sodium thiosulfate, twice with saturated aqueous sodium bicarbonate and once with brine. The dichloromethane layer is dried over magnesium sulfate and concentrated in vacuo to give crude 8 (0.704 g, >100%), which is contaminated with traces of residual 3-chlorobenzoic acid. The crude product is re-dissolved in ethyl acetate and washed three times with a saturated aq. sodium bicarbonate, dried using magnesium sulfate and concentrated in vacuo to give a tan solid. The residue is dissolved in THF, and the light brown solution was filtered through a plug of Magnesol. The filter pad is washed well with THF, and the colorless filtrate is concentrated in vacuo to give 8 as a white solid.

Herkunft & Nachweise