Cesium carbonate → Ethyl 6-(benzenesulphonylmethyl)-2-[2-(t-butoxycarbonyl)aminoethoxy]-3-(furan-3-yl)benzoate

Participants

Reaction Steps

A solution of 2-[N-(t-butoxycarbonyl)amino]ethyl bromide (0.032 g) in DMF (0.5 ml) was added to a stirred cooled solution of ethyl 6-(benzenesulphonylmethyl)-3-(furan-3-yl)-2-hydroxybenzoate (Intermediate 36, 0.05 g) and cesium carbonate (0.065 g) in DMF (0.5 ml) at 0° C. The resultant mixture was allowed to warm to room temperature, stirred for 3 hours then partitioned between ethyl acetate and water. The organic layer was washed with water, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 20-25% to give ethyl 6-(benzenesulphonylmethyl)-2-[2-(t-butoxycarbonyl)amino-ethoxy]-3-(furan-3-yl)-benzoate (0.031 g) as a colourless gum.

Provenance & Evidence