Ethyl Acetoacetate → 6-chloro-7-methoxy-2-methylquinolin-4(1H)-one

Participants

Reaction Conditions

Reaction Steps

A solution of 5-amino-2-chloroanisole (10.0 g, 63.5 mmol), ethyl acetoacetate (8.1 ml, 63.5 mmol) and catalytic para-toluene sulfonic acid (302 mg, 1.59 mmol) in 65 ml benzene over 4 A molecular sieves was stirred 6 hours at reflux (90° C. external temperature). The reaction mixture was then filtered and concentrated in vacuo. A mixture of the resulting residue and 6.4 ml DOWTHERM A was heated to 250° C. for 20 min. The reaction mixture was cooled to room temperature, and the precipitate was washed with hexanes and ethyl acetate to give 6.43 g (45% yield) of 6-chloro-7-methoxy-2-methylquinolin-4(1H)-one as a light brown solid. 1H NMR (400 MHz, DMSO-d6) δ 11.54 (bs, 1H), 7.94 (s, 1H), 7.02 (s, 1H), 5.86 (s, 1H), 3.94 (s, 3H), 2.31 (s, 3H).

Provenance & Evidence