Acetic Anhydride → HCID 19884847, compound

Participants

Reaction Steps

To a suspension of the compound of Example 6, (1.2 g, 2.7 mmoles) and dihydropyran (0.8 ml, 4.4 mmoles) in methylene chloride (20 ml) was added p-toluenesulfonic acid monohydrate (5 mg) The reaction mixture was stirred at room temperature for two hours. The solution was cooled to 0° and triethylamine (6 ml), 4-dimethylaminopyridine (DMAP) (15 mg) and acetic anhydride (5 ml) were added. The resulting solution stirred at room temperature for two hours. The solution was washed with 5% NaHCO3 (2×), water, 1N HCl and concentrated in vacuo. The residue was dissolved in THF (6 ml) and stirred with 1N HCl (1 ml) at room temperature for one hour. Dichloromethane (50 ml) and water (50 ml) were added to the solution and the organic layer was collected, washed with brine (4×) dried (Na2SO4) and concentrated in vacuo. The crystalline residue was washed with hexane and recrystallized to afford the title compound, m.p. 121°-123°.

Provenance & Evidence