Cesium carbonate → HCID 87730327, compound

Participants

Reaction Steps

To a solution of 2-bromo-4-bromomethyl-benzoic acid methyl ester (0.50g, 1.62 mmol) and 1-benzyl-1H-indole-3-carbaldehyde oxime (0.43 g, 1.70 mmol) in acetone (50 mL) was added cesium carbonate (2.12 g, 6.49 mmol). The mixture was heated to reflux for 6 hours and allowed to cool back to room temperature. The mixture was partitioned between ethyl acetate and brine and the layers were then separated. The aqueous layer was extracted with one additional portion of ethyl acetate. The organics were combined, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude material was purified by flash chromatography through silica gel using ethyl acetate/hexanes (0/100 gradient to 20/80) to give an off-white solid. This solid was recrystallized one time from ethyl acetate/hexanes (1/6) to give 4-[({[(1E)-(1-benzyl-1H-indol-3-yl)methylidene]amino}oxy)methyl]-2-bromobenzoic acid methyl ester (0.26 g, 34%) as off-white crystals. 1H NMR (400 MHz, CDCl3); δ 8.12 (s, 1H), 7.76 (m, 4H), 7.68 (s, 1H), 7.35 (d, 1H), 7.28 (m, 3H), 7.23 (m, 2H), 7.11 (d, 2H), 5.33 (s, 2H), 5.27 (s, 2H), 3.90 (s, 3H).

Provenance & Evidence