M-Cresol → 4-Tert-butyl-2-{5-[(3-cyano-5-hydroxyindol-1-yl)methyl]benzofuran-2-yl}thiazole

Participants

Reaction Steps

Trifluoroacetic acid (10 ml) was added to a mixture of 4-tert-butyl-2-{5-[(3-cyano-5-benzyloxyindol-1-yl)methyl]benzofuran-2-yl}thiazole (0.54 g), m-cresol (0.28 ml), thioanisole (0.28 ml) and ethanedithiol (0.56 ml) under ice-cooling. After being stirred for 4 hours, the mixture was poured into water (100 ml) and the resulting mixture was neutralized with aqueous sodium hydrogen carbonate solution and extracted with ethyl acetate. The organic layer was washed with water, brine successively, dried over magnesium sulfate and concentrated under reduced pressure. The resulting residue was subjected to column chromatography on silica gel and eluted with a mixture of toluene and ethyl acetate. The fractions containing the objective compound were combined and concentrated under reduced pressure to give 4-tert-butyl-2-{5-[(3-cyano-5-hydroxyindol-1-yl)methyl]benzofuran-2-yl}thiazole (305 mg).

Provenance & Evidence