Trifluoroacetic acid → 2,3-Dihydrobenzo(b)thiophene

Participants

Reaction Conditions

Reaction Steps

Trifluoroacetic acid (5.2 mL) was slowly added to the mixture of benzothiophene (1 g, 7.45 mmol) and triethylsilane (3.6 mL, 22.35 mmol) with heating under reflux at 50° C. for 125 hours. After cooling to 0° C., the reaction was quenched by addition of aq. saturated NH4Cl solution. The mixture was diluted with water and extracted with EtOAc. The organic layer was washed with brine, dried over anhydrous MgSO4, filtered and evaporated in vacuo. The residue was purified by silica gel column chromatography to provide the intermediate 112 (415 mg, 41%).

Provenance & Evidence