Hydrochloric Acid → 4'-Methyl-5-(2-oxo-2,3-dihydro-indol-1-yl)-biphenyl-3-carboxylic acid

Participants

Reaction Steps

The crude 4′-methyl-5-(2-oxo-2,3-dihydro-indol-1-yl)-biphenyl-3-carboxylic acid methyl ester from step 2 was in a mixture of methanol (3 mL), water (1 mL) and THF (1 mL), and 2M aqueous NaOH (0.4 mL) was added. The mixture was stirred for 2.5 hours, then neutralized by addition of 1N aqueous HCl. The mixture was concentrated under reduced pressure and co-evaporated with toluene three times to afford crude 4′-methyl-5-(2-oxo-2,3-dihydro-indol-1-yl)-biphenyl-3-carboxylic acid, which was used directly in the next step.

Provenance & Evidence