Cesium carbonate → 5-(pyrrolidin-1-yl)-1H-indole

Participants

Reaction Conditions

Reaction Steps

t-Butyl 5-bromo-1H-indole-1-carboxylate (200 mg, 0.68 mmol) was placed in a 10 mL sealed tube. Cs2CO3 (440 g, 1.35 mol) was then added, followed by CuI (13 mg, 0.07 mmol), L-proline (16 mg, 0.14 mmol), DMSO (3 mL), and pyrrolidine (480 g, 6.75 mol). After sparging with nitrogen, the resulting solution was stirred at 95° C. for 18 hours. The mixture was extracted with ethyl acetate (3×40 mL), and the organic layers were combined and washed with brine. The residue was purified by column chromatography using 1:5 and 1:2 ethyl acetate/petroleum ether solvent systems. The collected fractions were combined and concentrated to give 100 mg (80%) of 5-(pyrrolidin-1-yl)-1H-indole as brown oil.

Provenance & Evidence