Triethylsilane → 1-[5-(2-Bromopropyl)-2,3-dihydro-1H-indol-1-yl]ethanone

Participants

Reaction Steps

To a solution of 1-acetyl-5-(2-bromopropionyl)indoline (210 g) in trifluoroacetic acid (700 ml) was added triethylsilane (190 g) over a period of 30 minutes with stirring under ice cooling, the mixture was stirred for 30 minutes under ice cooling, and then for 1 hour at room temperature. After the reaction mixture was concentrated under reduced pressure, the residue was poured into water (2 l), and to the mixture was added hexane (500 ml) and stirred. The precipitates were collected by filtration, washed with hexane, and recrystallized from ethyl acetate-hexane to give 153 g of 1-acetyl-5-(2-bromopropyl)indoline melting at 124°-126° C.

Provenance & Evidence