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To a solution of 3.0 grams of ethyl 6-acetamidochromane-2-carboxylate (Example 12) dissolved in 20 mL of dry ether is added dropwise a solution of 1 mL of lithium aluminum hydride (70% in benzene) dissolved in about 2 mL of dry ether, and the solution is refluxed for about 1 h. An additional 1 mL of lithium aluminum hydride is added to the mixture, and the mixture refluxed for an additional 1-2 h. The reaction mixture is cooled to 0° C. and the excess hydride quenched by adding 10-12 mL of 1 N H2SO4, followed by 100 mL of water. The precipitate is filtered and washed well with ether. The aqueous phase is separated, extracted several times with 60-mL aliquots of ether. The combined extracts are washed with water and dried over anhydrous MgSO4. Evaporation to dryness under vacuum affords about 2.4 g of 6-acetamido-2-hydroxymethylchromane (about 90% yield).

1. temperaturethe solution is refluxed for about 1 h
2. temperaturethe mixture refluxed for an additional 1-2 h
3. customthe excess hydride quenched
4. additionby adding 10-12 mL of 1 N H2SO4
5. filtrationThe precipitate is filtered
6. washwashed well with ether
7. customThe aqueous phase is separated
8. extractionextracted several times with 60-mL aliquots of ether
9. washThe combined extracts are washed with water
10. dry with materialdried over anhydrous MgSO4
11. customEvaporation to dryness under vacuum