Ammonium Chloride → 5,7-dimethyl-8-methoxy-9-(2,2-diethoxyethyl)-1,2,3,4-tetrahydro-9H-fluorene

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Reaction Steps

19 Milliliters of a 15% n-butyl lithium n-hexane solution was added dropwise to a tetrahydrofuran solution containing 5.0 g of 5,7-dimethyl-8-methoxy-2,3,4,4a-tetrahydro-1H-fluorene in 50 ml of tetrahydrofuran at -50° C. After stirring at the same temperature for 40 minutes, thereto was added dropwise 6 ml of bromoacetoaldehyde diethyl acetal at the same temperature, followed by stirring at the same temperature for 1.5 hour. To the reaction mixture was added a saturated aqueous ammonium chloride solution and this was diluted with diethyl ether, washed with water twice and then with a saturated aqueous sodium chloride solution and then dried with magnesium sulfate. The solvent was distilled off and the residue was purified by a silica gel column chromatography (eluent: ethyl acetate:n-hexane=1:30) to obtain 5.68 g of 5,7-dimethyl-8-methoxy-9-(2,2-diethoxyethyl)-1,2,3,4-tetrahydro-9H-fluorene.

Provenance & Evidence