(Triethylsilyl)acetylene → 5-[(Triethylsilyl)ethynyl]-1H-indole

Participants

Reaction Steps

To a stirred solution of 5-iodoindole (0.50 g, 2.0 mmol) and (triethylsilyl)-acetylene (0.58 g, 4.0 mmol) in diisopropylamine (15 mL) was added Pd(PPh3)2Cl2 (0.07 g, 0.10 mmol) and CuI (0.04 g, 0.20 mmol) and the reaction mixture was stirred at r.t. for 16 h. The solvent was then removed in vacuo. EtOAc (15 mL) and water (15 mL) were added and the layers separated. The aqueous layer was extracted with EtOAc (2×10 mL). The combined organic layers were washed with water (2×20 mL), dried (Na2SO4), filtered and concentrated in vacuo. Purification by column chromatography (SiO2, 10% EtOAc/hexanes) gave the title compound (0.52 g, quantitative). δH (DMSO-d6) 11.30 (1H, br. s), 7.69 (1H, s), 7.45-7.41 (1H, m), 7.37 (1H, d, J 8.4 Hz), 7.15 (1H, dd, J 8.4 and 1.5 Hz), 6.48-6.40 (1H, m), 1.02 (9H, t, J 7.8 Hz), 0.65 (6H, q, J 7.9 Hz). MS (ES−) 254.0 (M−H)−.

Provenance & Evidence