Tetrahydrofuran → HCID 22870807, compound

Participants

Reaction Steps

To a solution containing (3S-trans)-α-amino-N-(6-cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl)benzeneacetamide (600 mg, 1.7 mmol; isomer B of the title compound of Example 2)in tetrahydrofuran (7 mL) at room temperature was slowly added excess acetyl chloride while maintaining the reaction at pH ~8.5 by simultaneous addition of 7% sodium carbonate solution. After the completion of the reaction, it was diluted with ethyl acetate and washed with water and brine. After drying over anhydrous magnesium sulfate, the solvent was evaporated to provide a colorless gum (518 mg, 77.2%) which was stirred with ether to give (3S-trans)-N-[2-[(6-cyano-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-4-yl)amino]-2-oxo-1-phenylethyl]acetamide, mp 133°-145° C. (starts shrinking@124° C). Analysis calculated for C22H23N3O4.0.4H2O: C, 65.95; H, 5.99; N, 10.49. Found: C, 66.09; H, 5.92; N, 10.30. [α]D =+62.4° (c=0.5, MeOH).

Provenance & Evidence