Trifluoroacetic acid → 4-Oxo-3-(quinolin-3-yl)-butyric acid ethyl ester

Participants

Reaction Steps

A solution of 22-3 (1.0 g, 3.7 mmol), TFA (0.06 mL, 3.9 mmol), and sudan red (0.5 mg) in anhydrous CH2Cl2 (50 mL) was cooled to −78° and treated with O3 until the sudan red color disappeared (5 min). Solid Ph3P (1.4 g, 5.6 mmol) was added and the solution warmed to room temperature. After 30 min., the solution was washed with sat. NaHCO3, dried, filtered, and evaporated. Chromatography on silica gel (10% acetone/EtOAc) afforded 22-4 as colorless glass.

Provenance & Evidence