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A mixture of pyridine-2-carboxaldehyde (151 g, 1.41 mol), ethylene glycol (157 mL), and 56 g (0.29 mol) of p-toluenesulfonic acid monohydrate in 1.4 L of toluene placed in a 5 L flask fitted with a Dean Stark trap was heated to reflux for 16 h, removing 50 mL of water. The mixture was concentrated in vacuo to a 800 mL volume, cooled, saturated sodium hydrogen carbonate solution was added (to pH 8-9), the layers were separated and the aqueous layer was washed with 100 mL of toluene. The combined organic layer was dried over magnesium sulfate, concentrated in vacuo, and distilled (with a short distilling head) to afford 119.5 g of 2-(1,3-dioxolan-2-yl)-pyridine (Formula V: R1 =H) as a pale oil, b.p. 100° C./1 mm.

1. customplaced in a 5 L flask
2. customfitted with a Dean Stark trap
3. temperaturewas heated
4. temperatureto reflux for 16 h
5. customremoving 50 mL of water
6. concentrationThe mixture was concentrated in vacuo to a 800 mL volume
7. temperaturecooled
8. additionsaturated sodium hydrogen carbonate solution was added (to pH 8-9)
9. customthe layers were separated
10. washthe aqueous layer was washed with 100 mL of toluene
11. dry with materialThe combined organic layer was dried over magnesium sulfate
12. concentrationconcentrated in vacuo
13. distillationdistilled (with a short distilling head)