Benzaldehyde → 3-methyl-3-phenylmethyl-1,3-dihydro-2H-indol-2-one

Participants

Reaction Conditions

Reaction Steps

3-Phenylmethyl-1,3-dihydro-2H-indol-2-one (prepared from 1,3-dihydro-2H-indol-2-one (4 g, 18.25 mmol) and benzaldehyde by the method of Daisley and Walker J. Chem. Soc. (C) (1971) page 1373) and tetramethylethylenediamine (4.5 g, 38.7 mmol) was dissolved in freshly distilled tetrahydrofuran under nitrogen and cooled to -75° C. in an acetone/dry ice bath. n-Butyllithium (2.5M, 20 ml, 50 mmol) was added and the mixture was stirred at -75° C. for 30 minutes. Iodomethane (2.84 g, 20 mmol) was added and the mixture was allowed to warm to room temperature. Water (5 ml) was added and the mixture was concentrated under reduced pressure to a yellow oil. Column chromatography on silica gel (eluent ethyl acetate/hexane) gave 3-methyl-3-phenylmethyl-1,3-dihydro-2H-indol-2-one as a yellow oil which solidified on standing.

Provenance & Evidence