Hydrochloric Acid → 5-Ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic Acid

Participants

Reaction Conditions

Reaction Steps

5-Ethoxyimino-4-hydroxy-5,6,7,8-tetrahydroquinoline-3-carboxylic acid ethyl ester (2.0 g) was dissolved in a mixture of 20 ml of 1 N sodium hydroxide and 10 ml of ethyl alcohol. The resulting reaction mixture was stirred at 90° C. for 2 hours. Under cooling with ice, the reaction mixture was adjusted to pH 4 with dilute hydrochloric acid. The crystals so precipitated were separated by filtration to obtain a yield of 0.95 g of the desired compound. This compound melted (and decomposed) at 225°-228° C. (uncorrected values). Its infrared absorption spectrum (KBr tablet) had absorption peaks at 3440, 2910, 1690, 1640, 1400, 1060, and 825 cm-1, and its n.m.r. spectrum (CF3COOH, 60MC, TMS) had signals at δ values of 1.57 (3H, t, J=7.5 Hz), 2.0-2.6 (2H, m), 3.0-3.5 (4H, m), 4.59 (2H, q, J=7.5 Hz), and 8.94 (1H, s).

Provenance & Evidence