Hydrochloric Acid → Indoline

Participants

Reaction Steps

The appropriately substituted intermediate indoles (5) are dissolved in trifluoroacetic acid and are treated with triethylsilane at 45°-50° C. for 48-96 hours, or are heated at reflux in ethanol for 48 hours in the presence of tin and hydrochloric acid, and in each case the mixture is then poured onto cracked ice. The resultant mixtures are made basic and are extracted with solvents such as chloroform, methylene chloride, or ethyl acetate. The extracts are evaporated to give the substituted-2-methyl-3-[2-(4-phenylpiperidino), (4-phenyl-1-piperazinyl) and [4-(2pyridyl)-1-piperazinyl]ethyl]-indoline compounds (6). The acid salts are obtained by treating the indoline (6) with hydrogen chloride in a solvent such as ethyl ether, ethyl acetate, or ethanol.

Provenance & Evidence