Aluminium lithium hydride → N-[2-(Hydroxymethyl)-3,4-dihydro-2H-1-benzopyran-6-yl]acetamide

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence