Diisopropylethylamine → Benzo[1,3]dioxole-5-carboxylic acid (7-chloro-2-oxazol-2-yl-4-oxo-1-phenyl-1,4-dihydro-quinolin-3-ylmethyl)-amide

Participants

Reaction Steps

In a 20 mL vial, 3-(aminomethyl)-7-chloro-2-(oxazol-2-yl)-1-phenylquinolin-4(1H)-one (intermediate A) (20 mg, 0.057 mmol), benzo[d][1,3]dioxole-5-carbonyl chloride (12 mg, 0.065 mmol) and N,N-(dimethylamino)pyridine (DMAP) (1.0 mg, 0.085 mmol) were combined with methylene chloride (1.5 mL) to give a brown solution. N,N-diisopropylethylamine (37 mg, 0.050 mL, 0.28 mmol) was added. The reaction mixture was stirred overnight at room temperature. In the morning, LC/MS indicated complete conversion to the desired product. The reaction mixture was diluted with 10 mL methylene chloride, then the organic solution was washed with water. The organic phase was dried over Na2SO4, filtered, then concentrated over silica gel. The silica gel-supported crude product was loaded onto a 25 gram SiliCycle column. Flash chromatography (50% ethyl acetate-hexanes ramped to 75% ethyl acetate-hexanes) afforded benzo[1,3]dioxole-5-carboxylic acid (7-chloro-2-oxazol-2-yl-4-oxo-1-phenyl-1,4-dihydro-quinolin-3-ylmethyl)-amide as a brown oil. 1H NMR (300 MHz, chloroform-d) δ ppm 8.36 (d, J=8.67 Hz, 1H) 7.50 (d, J=0.94 Hz, 1H) 7.34-7.42 (m, 4H) 7.30 (dd, J=8.67, 1.88 Hz, 1H) 7.15-7.26 (m, 6H) 7.05 (d, J=0.94 Hz, 1H) 6.77 (d, J=1.88 Hz, 1H) 6.70 (d, J=8.10 Hz, 1H) 5.91 (s, 2H) 4.37 (s, 2H). MS calcd. for C27H18ClN3O5 [(M+H)+] 499.9, obsd. 500.0.

Provenance & Evidence