Hexane → 7-Chloro-3-methyl-4-oxo-1-phenyl-1,4-dihydro-quinoline-2-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of N-(5-chloro-2-propionyl-phenyl)-N-phenyl-oxalamic acid methyl ester (15.0 g, 43.5 mmol) in methanol (200 mL) was added potassium carbonate (35.0 g, 253 mmol) at room temperature. The mixture was heated at 80° C. for 1 hr. Completion of the reaction was monitored by silica TLC (mobile phase; hexane:ethyl acetate=7:3; Rf=0.6). The reaction mixture was cooled to room temperature. The reaction mixture was filtered through a sintered glass funnel and the solids were washed with MeOH (2×50 mL). The combined filtrates were concentrated under reduced pressure. The residue obtained was taken up in ethyl acetate (500 mL), washed with water (2×200 mL), dried over anhydrous Na2SO4, and concentrated under reduced pressure. The crude material was purified by washing with a mixture of hexane-ether to afford 7-chloro-3-methyl-4-oxo-1-phenyl-1,4-dihydro-quinoline-2-carboxylic acid methyl ester (10.5 g, 73.4% yield). 1H NMR (DMSO-d6) δ 8.24 (d, J=8.7 Hz, 1H) 7.28-7.78 (m, 6H) 6.69 (d, J=1.7 Hz, 1H) 3.49 (s, 3H) 1.97 (s, 3H); MS calcd. for C18H14ClNO3 [(M+H)+] 328.0, obsd. 327.9.

Provenance & Evidence