反应详情

A solution of 0.59 g of 4,6-di-t-butyl-5-hydroxy-2-hydroxymethyl-2-methyl-2,3-dihydrobenzofuran synthesized in Example 48 and 1.17 ml of 2,6-luthidine in 5 ml of dichloromethane was cooled to 0° C. under nitrogen, combined with 1.25 ml of trimethylsilyl trifluoromethanesulfonate and stirred. After 30 minutes, the reaction solution was poured into water and extracted with ether, and the combined organic layers were concentrated. The residue was dissolved in 10 ml of THF, 5% hydrochloric acid was added and the solution was stirred for 1 hour, after which the reaction solution was concentrated and extracted with water and ether. The combined organic layers were washed with a saturated aqueous sodium bicarbonate solution, dried over anhydrous magnesium sulfate and then concentrated. The residue was purified by silica gel column chromatography eluting with n-hexane containing 9% ethyl acetate to give 0.62 g of 4,6-di-t-butyl-2-hydroxymethyl-2-methyl-5-trimethylsilyloxy-2,3-dihydrobenzofuran as a colorless oil (yield 84%).

1. extractionextracted with ether
2. concentrationthe combined organic layers were concentrated
3. dissolutionThe residue was dissolved in 10 ml of THF
4. addition5% hydrochloric acid was added
5. stirringthe solution was stirred for 1 hour
6. concentrationafter which the reaction solution was concentrated
7. extractionextracted with water and ether
8. washThe combined organic layers were washed with a saturated aqueous sodium bicarbonate solution
9. dry with materialdried over anhydrous magnesium sulfate
10. concentrationconcentrated
11. customThe residue was purified by silica gel column chromatography
12. washeluting with n-hexane containing 9% ethyl acetate