反应详情

A mixture of 0.1 mole of 2,2,8-trimethyl-4H-1,3-dioxino[4,5-c]pyridine-5-carboxaldehyde, 0.11 mole of triphenylphosphine and 0.11 mole of sodium chlorodifluoroacetate in 100 ml. of diglyme is heated under nitrogen at 90° for 24 hours. The reaction mixture is then filtered and concentrated in vacuo. Chromatography of the residue on silica gel and elution with ether-petroleum ether (10-50%) gives 5-(2,2-difluorovinyl)2,2,8-trimethyl-4H-1,3-dioxino[4,5-c]pyridine.

1. filtrationThe reaction mixture is then filtered
2. concentrationconcentrated in vacuo
3. washChromatography of the residue on silica gel and elution with ether-petroleum ether (10-50%)