2-Thiophenecarboxaldehyde → HCID 69926893, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 1.114 g (6.66 mmol) 5,6-diamino-nicotinic acid methyl ester in 40 ml dioxane was treated with 1.578 g (7.33 mmol) O-mesitylenesulfonylhydroxylamine (prepared from ethyl-o-mesitylenesulfonylacetohydroxamate and HClO4 (70%)) for 1 h at room temperature. 0.897 g (8 mmol) thiophene-2-carboxaldehyde and molecular sieves 4 Å was added and heated to 100° C. for 4 h before addition of 1.6 ml 5M KOH in methanol. The mixture was heated to 70° C. for 2 h and stirred at room temperature for 14 h. The volatiles were removed under reduced pressure and the residue was purified by flash column chromatography on silica eluting with a mixture of ethyl acetate and n-hexane to yield after evaporation 0.88 g (48%) of the title compound.

Provenance & Evidence