2,5-Dimethoxytetrahydrofuran → ethyl 1-benzyl-3-phenyl-5-(1H-pyrrol-1-yl)-1H-indole-2-carboxylate

Participants

Reaction Steps

A solution of ethyl 5-amino-1-benzyl-3-phenyl-1H-indole-2-carboxylate (0.74 g, 2 mmol), 2,5-dimethoxytetrahydrofuran (0.40 g, 3 mmol) in acetic acid was heated to 90° C. for 3 h. The reaction was cooled and concentrated. The residue was then purified by flash silica gel chromatography (hexanes/ethyl acetate 5/1) to afforded 0.8 g (95%) of ethyl 1-benzyl-3-phenyl-5-(1H-pyrrol-1-yl)-1H-indole-2-carboxylate as an off-white solid: 1H NMR (CDCl3) δ 0.97 (t, J=7.1 Hz, 3 H), 4.11 (q, J=7.1 Hz, 2 H), 5.84 (s, 2 H), 6.30 (t, J=2.1 Hz, 2 H), 7.01 (t, J=2.1 Hz, 2 H), 7.10-7.50 (m, 13 H); MS (ESI) m/z 421 (MH+); HRMS calcd for C28H25N2O2: 421.1917; found (ESI+): 421.1903; Anal. calcd for C28H24N2O2: C, 79.98; H, 5.75; N, 6.66. Found: C, 80.03; H, 5.67; N, 6.49.

Provenance & Evidence