Tetrahydrofuran → 3-(6-Ethyl-1H-indol-3-yl)-4-(1-methyl-1H-indol-7-yl)pyrrole-2,5-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-(1-methyl-1H-indol-7-yl)acetamide (370 mg, 1.97 mmol) and methyl 2-(6-ethyl-1H-indol-3-yl)oxoacetate (446 mg, 1.93 mmol) in DMF (8.0 mL) at 4° C. under N2, was added a 1.0 M solution of potassium tert-butoxide in THF (6.0 mL, 6.0 mmol) dropwise over 20 min. The reaction was heated to 50° C. and stirred for 7 h at this temperature. The reaction mixture was then cooled to room temp and quenched with 1.0 N hydrochloric acid (5.0 mL), extracted with EtOAc (2×15 mL), washed with saturated NaHCO3 (30 mL), saturated NaCl (30 mL), dried (MgSO4), filtered and concentrated. Flash chromatography (SiO2, 50% EtOAc/hexanes containing 1% TEA) gave the title compound (214 mg, 30%) as a red solid, mp 98–100° C. 1H NMR (DMSO-d6) δ 11.69 (s, 1H), 11.06 (s, 1H), 7.78 (m, 1H), 7.60 (m, 1H), 7.28 (m, 1H), 7.16 (s, 1H), 6.95 (m, 1H), 6.86 (m, 1H), 6.50 (m, 1H), 6.32 (m, 1H), 6.20 (m, 1H), 3.69 (s, 3H), 3.32 (m, 2H), 1.11 (m, 3H). MS (ESI, negative mode): m/z=368 [C23H19N3O2−H]−

Provenance & Evidence