反应详情

OsO4 (2.5 wt. % sol. in tert-Butanol) (0.86 mL, 0.0027 mol) was added to a stirred solution of 5-(but-2-yn-1-yloxy)-3-methyl-2-vinylpyridine (5.1 g, 0.027 mol) in acetone/water (100:100 mL) at 0° C. The reaction mixture was allowed to stir for 30 min at ambient temperature. Then NaIO4 (23.2 g, 0.108 mol) was added and the reaction mixture was allowed to stir for additional 4 h at ambient temperature. The reaction mixture was diluted with ice cold water (200 mL) and extracted with EtOAc (3×200 mL). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude residue was purified by flash column chromatography on silica gel, eluting with 5-10% EtOAc in pet ether to give 5-(but-2-yn-1-yloxy)-3-methylpicolinaldehyde as an off white solid (3.6 g, 69.9%). MS m/z=189.9 [M+H]+.

1. stirringto stir for additional 4 h at ambient temperature
2. extractionextracted with EtOAc (3×200 mL)
3. washThe combined organic layers were washed with brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated under reduced pressure
6. customThe crude residue was purified by flash column chromatography on silica gel
7. washeluting with 5-10% EtOAc in pet ether