Sodium ethoxide → 3-(1H-indol-5-yl)-5-(4-phenyl-5-(trifluoromethyl)thiophen-2-yl)-1,2,4-oxadiazole

Participants

Reaction Conditions

Reaction Steps

D1 (174 mg) and methyl 4-phenyl-5-(trifluoromethyl)-2-thiophenecarboxylate (286 mg) were combined, treated with sodium ethoxide (21% wt in EtOH, 411 ul) and heated to 120° C. in a microwave reactor for 30 minutes. LCMS analysis showed the reaction was incomplete so microwave heating was continued for a further two periods of 30 minutes. The reaction mixture was then cooled to RT, quenched with H2O (2 ml) and evaporated to dryness under reduced pressure to give the crude product (411 mg) as a brown solid. The crude residue was purified on a 40+S Biotage cartridge, eluting with a 0 to 50% mixture of Et2O in petroleum ether. This gave the title compound (122 mg) as an off-white solid. δH (CDCl3, 400 MHz): 6.68 (1H, s), 7.30 (1H, t), 7.41-7.55 (6H, m), 7.92 (1H, s), 7.99 (1H, d), 8.36 (1H, br. s), 8.50 (1H, s). MS (ES): C21H12F3N3OS requires 411; found 410 (M−H+).

Provenance & Evidence