A solution of {4-[(E)-2-(2-chloro-6-methoxy-phenyl)-vinyl]-3-nitro-phenyl}-carbamic acid tert-butyl ester (240 mg, 0.59 mmol) in triethyl phosphite (5.0 ml) was refluxed for 3 h. The reaction mixture was cooled to 25° C., and poured into water. The aqueous phase was extracted three times with ethyl acetate. The combined organic layers were washed with brine and dried over magnesium sulfate. Filtration followed by concentration in vacuo gave a brown solid. Flash chromatography (70/30 hexanes/ethyl acetate) afforded [2-(2-chloro-6-methoxy-phenyl)-1H-indol-6-yl]-carbamic acid tert-butyl ester (140 mg, 63%) as a white solid. MH+ 373.0.
