Potassium Hydroxide → 5-Fluoro-1-(pyridin-4-ylmethyl)-1H-indole-2-carboxylic acid

Participants

Reaction Steps

A solution of 2.1 g (7.04 mmol) of ethyl 5-fluoro-1-[(pyridin-4-yl)methyl]-1H-indole-2-carboxylate (WO 2007/010144) and of 1.18 g (21.12 mmol) of potassium hydroxide in 80 ml of ethanol and 2 ml of water is refluxed for 2 hours. The reaction mixture is subsequently concentrated under reduced pressure. 100 ml of water are added and the pH of the solution is brought to pH 8 by the addition of a concentrated hydrochloric acid solution. A precipitate is recovered by filtration and is washed with water and then dried under reduced pressure. 1.5 g of the expected product are thus obtained.

Provenance & Evidence