1-Isocyanato-2-phenylbenzene → biphenyl-2-yl-carbamic acid 2-(2-oxo-2,3-dihydro-1H-indol-4-yl)-ethyl ester

Participants

Reaction Conditions

Reaction Steps

2-Biphenylyl isocyanate (1.15 mL, 6.7 mmol) was added dropwise to a stirred mixture of 4-(2-hydroxy-ethyl)-1,3-dihydro-indol-2-one (709 mg, 4 mmol) in tetrahydrofuran (8 mL), dimethylforamide (2 mL) and pyridine (3 drops) under nitrogen atmosphere. The mixture was heated at 80° C. for 15 hours. The reaction was cooled, quenched with 1 N sodium hydroxide solution (100 mL) and extracted with ethyl acetate (200 mL). The organic layer was washed with brine, dried over anhydrous sodium sulfate and concentrated. The residue was chromatographed on silica gel eluting with ethyl acetate:hexane 3:2 to give 1.188 g (80%) of biphenyl-2-yl-carbamic acid 2-(2-oxo-2,3-dihydro-1H-indol-4-yl)-ethyl ester as a white fluffy solid.

Provenance & Evidence