Triethylsilane → 4-Chloroindoline

Participants

Reaction Conditions

Reaction Steps

4-Chloroindole (3.15 g) was dissolved in trifluoroacetic acid (32 ml), thereto was added triethylsilane (8.3 ml) and the mixture was heated at 50° C. with stirring for 30 minutes. The resultant mixture was cooled to room temperature, and trifluoroacetic acid was evaporated under reduced pressure. To the residue was added a saturated aqueous sodium hydrogen carbonate solution, and the mixture was extracted with ethyl acetate twice. The organic layer was dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=100:0-80:20) to give 4-chloro-2,3-dihydro-(1H)-indole (2.89 g) as colorless oil. APCI-Mass m/z 154/156 (M+H) (2) The above 4-chloro-2,3-dihydro-(1H)-indole was treated in a manner similar to described in Eur. J. Med. Chem. (2004) 39, 453-458 to give the title compound. APCI-Mass m/z 314/316 (M+H)

Provenance & Evidence