174775-48-5, Ethyl 5-aminobenzofuran-2-carboxylate is a benzofuran compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated
General procedure: An oven-dried Schlenk tube (A) equipped with a magnetic stir bar was charged with AgF (132.2 mg, 1.05 mmol, 3.5 equiv), sealed with a septum, and degassed by alternating vacuum evacuation and nitrogen backfill (three times) before freshly distilled EtCN (3 mL)was added. To the resulting suspension, which was precooled to -78 C (dry ice-acetone bath), was added TMSCF3 (149.3 mg, 1.05 mmol, 3.5 equiv) by microsyringe. The mixture was allowed towarm to r.t. and stirring was continued for an additional 15 min. In due course, AgF solid dissolved and a gray, dark solution of [Ag-CF3] formed. Another Schlenk tube (B) equipped with a magnetic stir bar was charged with the aniline (ArNH2; 0.30 mmol, 1.0 equiv) in freshly distilled EtCN (1.5 mL). To the resulting solution, which was precooled to 0 C (ice bath), aq HCl (12 M; 50.0 muL, 0.60mmol, 2.0 equiv) was added; precipitate formed immediately. After 5 min stirring, t-BuONO (37.7 mg, 0.33 mmol, 1.1 equiv) was added by microsyringe, and the mixture was allowed to stir at 0 C for 15 min. The resulting suspension in Schlenk tube (B) was degassed by alternating vacuum evacuation at -196 C (liquid nitrogen), then the solution was allowed to warm to r.t. under a nitrogen atmosphere (three times), and finally cooled to -78 C (dry ice-acetone bath). The gray, dark solution of [AgCF3] in Schlenk tube (A), which was precooled to -78 C (dry ice-acetone bath), was added to Schlenk tube (B) (ArN2+Cl-) by syringe at -78 C (dry ice-acetone bath) over a period of 1 h. After the addition was complete, the reaction mixture was stirred for 3 h at -78 C (dry ice-acetone bath), allowed to warm to r.t., and stirring was continued for an additional 1 h. An off-white precipitate was observed, and the reaction mixture was diluted with EtOAc (3 mL) and filtered through a short silica gel column. The solvent was removed under reduced pressure with a rotatory evaporator, and the crude residue was purified by silica gel column chromatography to give the desired trifluoromethylation product 3. The yields of products 3a, 3f, 3g, 3l, 3o, 3r, 3x, and 3zb are based on the 19F NMR spectra with 4-F3COC6H4OMe as internal standard. Analytical data for the representative product ethyl 4-(trifluoromethyl)benzoate (3i) are provided below. Data for other products can be found in the literature.