Piperidine → HCID 135834136, compound

Participants

Reaction Steps

A solution of tert-butyl 5-{[tert-butyl(dimethyl)silyl]oxy}-2-formylphenylcarbamate (12-4, 0.57 g, 2.4 mmol, 1 equiv), ethyl 1H-benzimidazol-2-ylacetate (0.50 g, 2.4 mmol, 1.0 equiv, prepared by the method of Rahmouni, M, Derdour, A., Bazureau, J., and Hamelin Tetrahedron Lett. 1994, 35, 4563-4564), and piperidine (0.12 mL, 1.2 mmol, 0.5 equiv) in ethanol (50 mL) was heated at reflux for 20 h. The reaction mixture was cooled and concentrated. A solution of the residue and triethylamine trihydrofluoride (0.38 mL, 2.3 mmol, 0.97 equiv) in acetonitrile (30 mL) was stirred at 30° C. for 2.5 h. The precipitate which formed was filtered and air dried to give 3-(1H-benzimidazol-2-yl)-7-hydroxy-2(1H)-quinolinone (12-5) as an off-white solid. 1H NMR (400 MHz, DMSO-d6) δ 12.51 (s, 1H), 12.19 (s, 1H), 10.45 (br s, 1H), 8.95 (s, 1H), 7.76 (d, 1H, J=8.8 Hz), 7.68 (m, 1H), 7.59 (m, 1H), 7.18 (m, 2H), 6.82 (s, 1H), 6.75 (d, 1H, J=8.8 Hz).

Provenance & Evidence