Ammonia → Methyl 4-methoxy-2,3-dihydro-1H-indole-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

119 mg (4.90 mmol) of magnesium turnings are added to a solution of 500 mg (2.44 mmol) of 4-methoxy-1H-indole-2-carboxylic acid in 10 ml of methanol. The mixture is stirred for 3 hours in a bath at 110° C. and then for 1 hour at room temperature. 20 ml of hydrochloric acid are added at 0° C. and the mixture is stirred for one hour. 3 N ammonia solution is then added to pH 10 and the mixture is extracted with 3 times 50 ml of ethyl acetate. The organic phases are dried over magnesium sulfate, filtered and concentrated under reduced pressure. The evaporation residue is purified by chromatography on a silica column using a dichloromethane/ethyl acetate mixture (98/5, then 95/5; v/v) as the eluent to give the expected product in the form of a brown oil with a yield of 64%.

Provenance & Evidence