Water → HCID 22404794, compound

Participants

Reaction Steps

A solution of 39.27 g (0.217 mole) of 7-amino-2,3-dihydro-2,2-dimethyl-6-fluorobenzofuran in 750 mL of diethyl ether was cooled to -5° C to 0° C., and 23.54 g (0.217 mole) of t-butyl hypochlorite was added in a dropwise manner during a fifteen minute period. The temperature rose to 10° C., but was lowered to 0°-5° C. at which the reaction mixture stirred for 20 minutes. Gas chromatographic analysis showed that the reaction was incomplete, and an additional 4.54 g (0.042 mole) of t-butyl hypochlorite was added. The mixture was stirred at 0°-5° C. for an hour after which gas chromatographic analysis showed that the reaction was still incomplete. Therefore, an additional 1.82 g (0.017 mole) of t-butyl hypochlorite was added to the reaction mixture, and stirring was continued for one more hour. At the conclusion of this period the reaction was determined to have been completed, and it was poured into 400 mL of water. To this mixture was added 100 mL of 10% ammonium hydroxide. The aqueous and organic phases were separated. The aqueous phase was washed with diethyl ether, and this wash was combined with the organic phase. The combined material was dried over anhydrous sodium sulfate, filtered, and the solvent 20 evaporated from the filtrate under reduced pressure, leaving a dark red oil as the residue. This oil was passed through a column of silica gel, eluting with petroleum ether:diethyl ether (9:1). Product-containing fractions were combined, and the solvent was evaporated under reduced pressure, yielding 40.24 g of 7-amino-4-chloro-2,3-dihydro-2,2-dimethyl-6-fluorobenzofuran as a red oil. The NMR spectrum was consistent with the proposed structure.

Provenance & Evidence