4-bromo-1H-indole-2-carboxylic acid → 4-(2-Ethylphenyl)-indole-2-carboxylic acid

Participants

Reaction Steps

To a mixture of 0.28 g of 4-bromo-indole-2-carboxylic acid and 0.069 g of tetrakistriphenylphosphinepalladium in 11 ml of toluene and 2 ml of 2M soda is added a solution of 0.300 g of 2-ethylphenylboronic acid in 3 ml of ethanol. This mixture is refluxed for 16 h, filtered and the aqueous phase acidified with 2N HCl and extracted with ethyl acetate. Concentration of the organic phase gives the product as a brownish powder, m.p. 230-233°, sufficiently pure for the next step.

Provenance & Evidence