Dichloroacetic Acid → 3-Chloro-4-hydroxy-6-methyl-1-(2-propen-1-yl)-2(1H)-pyridinone

Participants

Reaction Steps

To a stirred solution of 1-allyl-4-hydroxy-6-methylpyridin-2(1H)-one (500 mg, 3.0 mmol) in CH3CN(10 ml), at rt, was added sequentially n-bromosuccinimide (440 mg, 3.3 mmol) and dichloroacetic acid (546 μl, 6.62 mmol). The resulting mixture was stirred for 2 h. The heterogeneous mixture was filtered and the solid was washed with additional CH3CN to give 350 mg (59%) of the desired product as a tan solid. 1H-NMR (DMSOd6/300 MHz) δ 11.16 (s, 1H), 5.98-5.86 (m, 2H), 5.12 (dd, J=10.5, 1.5 Hz, 1H), 4.89 (dd, J=17.1, 1.5 Hz, 1H), 4.63-4.61 (m, 2H), 2.29 (s, 3H). ES-HRMS m/z 200.050 (M+H calcd for C9H11ClNO2=200.0470)

Provenance & Evidence