Water → HCID 12148502, compound

Participants

Reaction Steps

10 g of 4-(benzo[1,3]dioxol-4-yl)-4-methyl-2-oxo-pentanoic acid is dissolved in 125 ml of dimethylacetamide and mixed with 3.5 ml of thionyl chloride under argon at −0° C. After 20 minutes of stirring at −3 to +3° C., 7.6 g of 6-amino-4-ethyl-2,3-benzoxazin-1-one (WO00/32584) is added. It is stirred for 96 hours at room temperature, then mixed with water, extracted with ethyl acetate, the organic phase is washed with water, dried (Na2SO4), and after the solvent is concentrated by evaporation and after chromatography of the crude product on silica gel with hexane/ethyl acetate (100:0→60:40), 6.56 g of 6-[4-(benzo[1,3]dioxol-4-yl)-4-methyl-2-oxo-valeroyl-amino]-4-methyl-2,3-benzoxazin-1-one is obtained as a beige solid.

Provenance & Evidence