Hydrochloric Acid → (Z)-3-{4-Oxo-2-[(2-oxoindolin-3-ylidene)methyl]-4,5,6,7-tetrahydro-1H-indol-3-yl}propanoic Acid

Participants

Reaction Steps

To an EtOH solution (3.0 mL) containing (Z)-3-((3-(3-ethoxy-3-oxopropyl)-4-oxo-4,5,6,7-tetrahydro-1 H-indol-2-yl)methylene)indolin-2-one (0.50 mmol) was added 3.0 N aqueous NaOH (1.0 mL). The reaction was heated at reflux for 2.0 h and cooled to room temperature. The solution was acidified with 6 N HCl to pH 3.0. The resultant precipitate was filtered and washed with MeOH to provide the desired product. 1 H NMR (DMSO-d6) δ 13.76 (s, 1 H), 11.01 (s, 1 H), 7.77 (s, 1 H), 7.76 (d, 1 H), 7.17 (dd, 1 H), 7.01 (dd, 1 H), 6.89 (dd, 1 H), 3.15 (t, 2 H), 2.91 (t, 2H), 2.36-2.41 (m, 2 H), 2.06 (t, 2 H).

Provenance & Evidence