3,4-dihydro-2H-pyran → HCID 18648593, compound

Participants

Reaction Steps

The thus obtained L-pyroglutamyl-L-prolinol (110 g, 0.519 mol) and dihydropyran (220 g, 2.62 mol) are dissolved in acetonitrile (2.75 l), and pyridine toluenesulfonate (11 g) is added under water-cooling. The mixture is stirred at room temperature for two days, and the reaction liquid is concentrated under reduced pressure, dissolved again in methylene chloride (1.5 l) and washed successively with 5% potassium carbonate (1 l) and water (1 l). The methylene chloride layer is dried over anhydrous magnesium sulfate and filtered. The filtrate is concentrated to dryness under reduced pressure to give N-pyroglutamyl-O-tetrahydropyranyl-L-prolinol (169 g, 110%).

Provenance & Evidence