反应详情

4-formyl-2-methoxyphenyl β-D-galactopyranoside (1c)(0.12 g, 0.38 mmol), 1,2-dimethylpyridinium iodide (0.12 g, 0.51 mmol) and methanolic sodium methoxide (1M, 0.38 ml, 0.38 mmol) in methanol (10 ml) was carefully heated until the reagents had completely dissolved, after which the reaction mixture was allowed to cool to room temperature. A yellow precipitate started to separate after about 2 h. The reaction mixture was left over-night (18 h), after which the precipitate was filtered off and washed well with methanol to give (17c)(0.11 g, 54%) as a fine yellow solid, m.p. 210°-230° C. (decomp.), [α]D -14° (c 1, DMSO).

1. dissolutionhad completely dissolved
2. customto separate after about 2 h
3. filtrationafter which the precipitate was filtered off
4. washwashed well with methanol