反应详情

A solution of 4 (123 mg, 0.58 mmol) and dihydropyran (0.22 mL, 2.33 mmol) in methylene chloride (2 mL) containing pyridinium tosylate (25 mg, 0.1 mmol) was stirred at room temperature for 20 hours. It was diluted with ether and washed with saturated aqueous sodium chloride. The separated aqueous layer was extracted once with ether and the combined ether layer was dried over magnesium sulfate. The crude product was purified on a silica gel column to give 170 mg of 7-bromo-1,6-bistetrahydropyranyl heptanyl ether (6). PMR (CDCl3): δ4.86-4.48 (m, 2H), 4.00-3.41 (m, 9H), 1.93-1.18 (m, 20H).

1. washwashed with saturated aqueous sodium chloride
2. extractionThe separated aqueous layer was extracted once with ether
3. dry with materialthe combined ether layer was dried over magnesium sulfate
4. customThe crude product was purified on a silica gel column