反应详情

To a stirred solution of N-(4-chloro-5-vinylpyridin-2-yl)acetamide (6 g, 30.5 mmol) and 2,6-lutidine (7.11 mL, 61.0 mmol) in a mixture of dioxane (110 mL) and water (25 mL) at 0° C. was added osmium tetroxide, 2.5 wt % solution in 2-methyl-2-propanol (9.58 mL, 30.5 mmol) followed by the addition of sodium periodate (19.58 g, 92 mmol) and the reaction was stirred for 4 h. The reaction mixture was diluted with water and extracted with ethyl acetate (2×100 mL). The combined organic layers were washed with brine solution, dried over sodium sulphate, concentrated under reduced pressure. The residue was purified by silica column using hexane/Ethyl acetate to yield N-(4-chloro-5-formylpyridin-2-yl)acetamide as an off-white solid (5.8 g, 28.1 mmol, 92% yield). LCMS (ESI) m/e 197.0 [(M)−, calcd for C8H6ClN2O2197.04] LC/MS retention time (method A): tR=1.21 min; 1H NMR (400 MHz, DMSO-d6) δ 11.20 (s, 1H), 10.18 (s, 1H), 8.76 (s, 1H), 8.27 (s, 1H), 2.16 (s, 3H).

1. extractionextracted with ethyl acetate (2×100 mL)
2. washThe combined organic layers were washed with brine solution
3. dry with materialdried over sodium sulphate
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by silica column