indium(III)bromide → Benzyl 4-(6-(5-bromo-4-(2-ethoxy-2-oxoethyl)thiophene-2-carbonyl)-1H-indol-2-yl)benzoate

Participants

Reaction Steps

To a 25 mL flask containing freshly distilled toluene (10 mL) was added benzyl 4-((2-amino-4-(5-bromo-4-(2-ethoxy-2-oxoethyl)thiophene-2-carbonyl)phenyl)ethynyl)benzoate (100 mg, 0.17 mmol) and indium tribromide (24 mg, 0.06 mmol) under N2. The resulting mixture was refluxed for one hour. The solvent was removed in vacuo. MPLC purification (Hex:EtOAc/4:1) of the crude product gave 4 as a yellow solid (76 mg, 76%). 1H NMR (400 MHz, CDCl3) δ 9.50 (brs, 1H), 8.16 (d, J=8.0 Hz, 2H), 8.02 (s, 1H), 7.82 (d, J=8.4 Hz, 2H), 7.65 (q, J=8.4 Hz, 2H), 7.55 (s, 1H), 7.48-7.34 (m, 5H), 6.98 (s, 1H), 5.39 (s, 2H), 4.19 (q, J=7.2 Hz, 2H), 3.64 (s, 2H), and 1.28 (t, J=7.2 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ 187.53, 170.09, 166.24, 143.98, 140.75, 136.91, 136.16, 136.07, 135.92, 135.09, 132.96, 131.53, 130.74, 129.74, 128.90, 128.59, 128.53, 125.56, 122.10, 121.94, 120.81, 113.74, 101.86, 67.14, 61.66, 35.37, and 14.43.

Provenance & Evidence