(S)-1-(4-Methoxyphenyl)ethylamine → methyl (1S)-1-{[(1S)-1-(4-methoxyphenyl)ethyl]amino}indane-5-carboxylate

Participants

Reaction Steps

To 713 mg of methyl 1-oxoindane-5-carboxylate were added 612 mg of (1S)-1-(4-methoxyphenyl)ethanamine, 0.23 ml of acetic acid, 600 mg of Molecular Sieves 4A, and 12 ml of toluene, followed by heating to reflux using a Dean-Stark type reflux device for 4 hours under reduced pressure (213 mbar). Then, 0.23 ml of acetic acid and 300 mg of Molecular Sieves 4A were added thereto, followed by heating to reflux using a Dean-Stark type reflux device for 4 hours under reduced pressure (213 mbar). The insoluble material was removed by filtration and the solvent was then evaporated under reduced pressure to obtain an intermediate product. To a solution of the obtained intermediate product in 13 ml of ethanol was added 161 mg of sodium borohydride under ice-cooling, followed by stirring for 1 hour under ice-cooling. The solvent was evaporated under reduced pressure, and to the obtained residue were added water, a saturated aqueous sodium hydrogen carbonate solution, and ethyl acetate to carry out a layer separation operation. The organic layer was washed with water and saturated brine in this order, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography to obtain 452 mg of methyl (1S)-1-{[(1S)-1-(4-methoxyphenyl)ethyl]amino}indane-5-carboxylate.

Provenance & Evidence