反应详情

According to Scheme 9 Step 2: A mixture of (Z)-3-(4-(4-chlorobenzyl)-6-methoxy-3,5-dioxo-4,5-dihydro-1,2,4-triazin-2(3H)-yl)-N′-hydroxybenzamidine (150 mg, 0.4 mmol), triethyl orthoacetate (2 mL) and of sulfuric acid (1 drop) was stirred at 100° C. 4 hours. The reaction mixture was quenched with water and extracted with ethyl acetate (×3). The combined organic layers were successively washed with water, brine, dried over MgSO4, filtered and concentrated. The crude product was purified by flash chromatography, 10 g prepacked column, cycloexane/ethyl acetate 80/20 to afford 4-(4-chlorobenzyl)-6-methoxy-2-(3-(5-methyl-1,2,4-oxadiazol-3-yl)phenyl)-1,2,4-triazine-3,5(2H,4H)-dione 4.146 (40 mg, Yield=25%) as a white solid.

1. custom4 hours
2. customThe reaction mixture was quenched with water
3. extractionextracted with ethyl acetate (×3)
4. washThe combined organic layers were successively washed with water, brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude product was purified by flash chromatography, 10 g