5-Chloroindole-3-carboxylic acid

A solution of 5.0 g (33.0 mmol) of commercially available 5-chloro-1H-indole in 50 ml dry DMF was kept at 0° C., while 7.35 g (35.0 mmol) trifluoroacetanhydride was added dropwise. After 3 h stirring at room temperature the mixture was poured into 200 ml water, and the precipitate was filtered with suction and heated with reflux overnight in 200 ml 20percent NaOH. It was extracted twice with dichloromethane, and the aqueous layer was acidified with hydrochloric acid. The crystalline title compound was collected by filtration and dried in vacuo. yield: 6.0 g (93percent)Solid 1-(5-chloro-1H-indol-3-yl)-2, 2, 2-trifluoroethanone (hd) (743 mg, 3.0 mmol) was suspended in 10 mL of a 4M aqueous solution of sodium hydroxide. The resulting mixture was stirred at reflux during 1 hour. The solution was extracted with diethyl ether (2x25 mL) and then the aqueous phase was acidified with an aqueous solution of 5M HCl to pH 1. The precipitate was filtered off, washed with water and dried in the presence of PSolid l-(5-chloro-1H-indol-3-yl)-2, 2, 2-trifuoroethanone (hd) (743 mg, 3.0 mmol) was suspended in 10 mL of a 4M aqueous solution of sodium hydroxide. The resulting mixture was stirred at reflux during 1 hour. The solution was extracted with diethyl ether (2x25 mL) and then the aqueous phase was acidified with an aqueous solution of 5M HC1 to pH 1. The precipitate was filtered off, washed with water and dried in the presence of P2O5 under reduced pressure. Pure 5- chloroindolic acid (2d) (480 mg, 2.45 mmol) was obtained as a beige solid. Yield: 82percent. 1H NMR (300 MHz, (CD

Molecular Weight:195.60
XLogP3:2.6
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:1
Exact Mass:195.0087061
Monoisotopic Mass:195.0087061
Topological Polar Surface Area:53.1
Heavy Atom Count:13
Complexity:222
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes