p-Toluenesulfonic acid → AG-G-89175

Participants

Reaction Steps

In dichloromethane (200 ml) was dissolved (S)-(-)-ethyl lactate (35.4 g), to which was added, under ice-cooling, p-toluenesulfonic acid.hydrate (570 mg). To the mixture was added dropwise 3,4-dihyro-2H-pyran (30.2 g), taking 30 minutes, followed by stirring for one hour under ice-cooling. To the reaction mixture was added a 5% aqueous solution of sodium hydrogen carbonate (50 ml), which was vigorously stirred, then the organic layer was separated. The organic layer was further washed with a 5% aqueous solution of sodium hydrogen carbonate and dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure to afford ethyl(2S)-2-(3,4,5,6-tetrahydro-2H-pyran-2-yloxy)propionate (61 g) as a pale yellow oily product.

Provenance & Evidence