Trifluoroacetic acid → 7-(Trifluoroacetylamino)-2,3-dihydrobenzofuran

Participants

Reaction Steps

2,3-dihydrobenzofuran-7-carboxylic acid (D1) (1.42 g) was dissolved in a mixture of trifluoroacetic acid (50 ml) and trifluoroacetic anhydride (10 ml). After stirring at room temperature for 1.5 h, the mixture was cooled to 0° C. and treated portionwise with sodium azide (788 mg, 1.4 eq.), then stirred at room temperature for 2 days under argon. The mixture was evaporated under reduced pressure, and the residue partitioned between CHCl3 and water. The organic phase was washed with K2CO3 (aq), dried (Na2SO4) and the solvent evaporated under reduced pressure, to give the title compound (1.64 g, 82%) as an off-white crystalline material.

Provenance & Evidence