Bromide ion → 2-Methyl-2-phenyl-5-methoxy-6,7-dichloro-1-indanone

Participants

Reaction Steps

A 35 ml glass pressure bottle, fitted with an efficient magnetic stirrer was charged with 25 ml of toluene. Methyl chloride (1.01 g, 20 mmole) were dissolved in the toluene and to this solution there were added 0.61 g (2 mmole) of 6,7-dichloro-5-methoxy-2-phenyl-1-indanone, 0.21 g (0.4 mole) of N-p-(trifluoromethylbenzyl) cinchoninium bromide and 5 ml of 50% aqueous sodium hydroxide. The reaction mixture was sealed with a screw cap and vigorously stirred for 18 hours at room temperature (22°-25° C.). The reaction mixture was then diluted with 25 ml of toluene and 15 ml of water. The aqueous layer was separated and the toluene layer was washed twice with 25 ml of 4N hydrochloric acid. An aliquot of the toluene solution was concentrated in vacuo to dryness on a rotary evaporator. An LC assay indicated a 98% yield while an NMR assay using the chiral shift reagent [tris-[3-heptafluoropropylhydroxymethylene)-d-camphorato]europium (III)] showed a (+):(-) isomer ratio of 95.3:4.7.

Provenance & Evidence