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A mixture of 0.55 g (0.3 mmol) 3-methoxy-6-nitro-pyridine-2-carbaldehyde, 0.8 ml (15 mmol) of ethylene glycol, and 10 mg (catalytic amount) of p-toluene sulfonic acid was refluxed in 50 ml of toluene using a Dean-Stark trap to trap water. After 90 minutes, the reaction mixture was cooled to room temperature and the solvent evaporated. The residue was chromatographed on silica using 5:1 (chloroform/ethyl acetate) as the elutant. Appropriate fractions were combined and evaporated to yield 0.6 g of 2-[1,3]dioxolan-2-yl-3-methoxy-6-nitro-pyridine as an oil. TLC: Rf=0.9 (1:1 chloroform/ethyl acetate). 1H NMR (CDCl3) δ 8.25 (d, 1H), 7.40 (d, 1H), 6.30 (s, 1H), 4.30 (m, 2H), 4.10 (m, 2H), 4.0 (s, 3H). Mass Spectrum: m/e=227.2 (p+1).

1. customthe solvent evaporated
2. customThe residue was chromatographed on silica using 5:1 (chloroform/ethyl acetate) as the elutant
3. customevaporated