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A mixture of 11.3 g (0.069 mol) of 2-methyl-nicotinic acid ethyl ester and 8.4 g (0.076 mol) of selenium dioxide in 150 mL of dioxane is refluxed under nitrogen for 4 hours. The reaction mixture is cooled to room temperature and filtered. The filtrate is evaporated and the residue is chromatographed on 400 grams of silica gel using 50/50 ethyl acetate/hexanes as the eluant. Appropriate fractions are combined to yield 5 g of 2-formyl-nicotinic acid ethyl ester. 1H NMR (CDCl3) δ10.3 (s, 1H), 8.8 (m, 1H), 8.0 (m, 1H), 7.5 (m, 1H), 4.30 (q, 2H), 1.4 (t, 3H). TLC (7/3 hexanes/ethyl acetate) Rf=0.2.

1. temperatureis refluxed under nitrogen for 4 hours
2. filtrationfiltered
3. customThe filtrate is evaporated
4. customthe residue is chromatographed on 400 grams of silica gel using 50/50 ethyl acetate/hexanes as the eluant