Cesium carbonate → HCID 59192506, compound

Participants

Reaction Steps

To a suspension of trifluoro-methanesulfonic acid 4-hydroxy-8-oxo-5,6,7,8-tetrahydro-naphthalen-2-yl ester (XXVIII, 177 mg, 0.57 mmol) and cesium carbonate (372 mg, 1.14 mmol) in acetonitrile (5 mL) was added tert-butyl bromoacetate (167 mg, 0.86 mmol) at room temperature under nitrogen. The resulting suspension was stirred for 15 h at room temperature, and then concentrated under vacuum. The residue was diluted with water (10 mL) and ethyl acetate (20 mL). The aqueous layer was separated and extracted with ethyl acetate (20 mL). The combined organic extracts were washed with brine (50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The crude product was purified by ISCO (40 g) column chromatography, (gradient elution with 5-25% ethyl acetate in hexanes) to provide (5-oxo-3-trifluoromethanesulfonyloxy-5,6,7,8-tetrahydro-naphthalen-1-yloxy)-acetic acid tert-butyl ester (143 mg, 59%) as a white solid: ES(+)-HRMS m/e calcd. for C17H19F3O7S (M+H)+425.0877, obsd. 425.0876.

Provenance & Evidence