Hydrochloric Acid → 8-Methoxy-6,6-dimethyl-11-oxo-6,11-dihydro-5H-benzo[b]carbazole-3-carbonitrile

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Reaction Steps

(Method 2) To the THF (5.6 ml) solution of 2-[1-(6-cyano-1-methanesulfonyl-1H-indol-2-yl)-1-methylethyl]-4-methoxy-benzoic acid methyl ester (Compound AA4, 138 mg, 0.324 mmol), tetrabutylammonium fluoride (514 mg, 6 eq.) was added, and the mixture was stirred at room temperature overnight. Thereafter, 2 M aqueous solution of sodium hydroxide (5.6 ml) was added to the mixture, which was then stirred for 4 hr, added with 1 M HCl, and extracted with ethyl acetate. The organic layer was washed with brine and dried over magnesium sulfate. The drying agent was removed by filtration and the residues obtained after concentration under reduced pressure were dissolved in ethyl acetate (10 ml) and added with e 4 M HCl and ethyl acetate solution (10 ml) followed by stirring at room temperature for 30 min. The residues obtained after concentration of the reaction solution under reduced pressure were purified by silica gel column chromatography (ethyl acetate/hexane) to obtain the title compound (89.2 mg, 62%).

Provenance & Evidence