Synthesis
At atmospheric pressure saturated with carbon monoxide, 5-iodo-2-hydroxyindole (17 g) was mixed with 2 g of
palladium diacetate, 18.2 triethylamine, 150 mL of methanol, 15 mL of dimethyl sulfoxide, and 2.6 g of DPPP was refluxed. after 24 h, the reaction mixture was filtered to remove the catalyst and the filtrate was concentrated. Make
The concentrate was chromatographed on silica gel using 30% ethyl acetate in hexane. The fraction containing the product was concentrated and allowed to stand. The product precipitates and is collected by vacuum filtration to give 0.8 g (7%) of as an off-white solid.
Methyl 5-carboxylate dihydroindol-2-one as an off-white solid.
