Methanol → 6-(Trifluoromethyl)indolin-5-ol

Participants

Reaction Steps

A mixture of 5-methoxy-6-trifluoromethylindoline (D3, 7.5 g, 34.3 mmol) and iodotrimethylsilane (12.5 ml, 89.3 mmol) in dry chloroform (70 ml) was heated under reflux for 65 h. Methanol was then added cautiously with stirring to the cooled mixture, and solvent was then removed in vacuo. The residue was treated with saturated sodium bicarbonate solution and water until basic, and then extracted with dichloromethane/methanol. The organic extract was washed with brine, dried and evaporated. The residue was extracted with ether in a Soxhlet apparatus, and concentration of the resultant solution gave the title compound in three crops (total 2.85 g, 41%), m.p.>180° (decomp.).

Provenance & Evidence