Triethylamine → HCID 178460078, compound

Participants

Reaction Steps

Following the procedures of Example 3, 2.0 g. (0.0096 mol) of 4-nitro-2-propionamidophenyl (prepared from propionic acid and 2-amino-4-nitrophenyl) is hydrogenated in a mixture of 100 ml. of ethanol, 0.3 g. of 10% palladium-on-carbon and 1.34 ml. of concentrated hydrochloric acid in a Parr apparatus. Filtration and evaporation of the solvent gives 4-amino-2-propionamidophenol hydrochloride. The latter (2.0 g., 0.0096 mol) in a methanol solution is treated with 1 equivalent of triethylamine under nitrogen atmosphere. The solution of the free amine is added to a refluxing mixture of one equivalent of 3,5-diacetyl-4,6-dihydroxy-2H-pyran-2-one and 30 ml. of methanol under nitrogen. The reaction mixture is refluxed for 18 hours, filtered and the solid is recrystallized from ethanol to yield 5-acetyl-4-hydroxy-3-[1-(4-hydroxy-3-propionamidophenylamino)ethylidene]-2H-pyran-2,6(3H)-dione, m.p. 228°-229° C. (dec.).

Provenance & Evidence