Potassium Carbonate → Ethyl 2-(7-hydroxy-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl)acetate

Participants

Reaction Conditions

Reaction Steps

DCM (305 mL) was transferred to a 1 L 3-necked round-bottomed flask and cooled to −11° C. (internal) (ice acetone bath). BBr3 (72.0 mL, 761 mmol) was added to the DCM with stirring. A solution of ethyl 2-(7-methoxy-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl)acetate (41.62 g, 152 mmol) in DCM (145 mL) was added in drops maintaining the internal temperature of about −5 to 0° C. After the addition the reaction was stirred for 1 h below about 0° C. The reaction mixture was slowly poured into mixture of ice (400 mL) and saturated K2CO3 (400 mL) and stirred well (pH maintained at 9-7). The organic layer was separated, washed with brine (1×100 mL), dried over MgSO4, filtered and concentrated under reduced pressure. The residual brown oil was purified by passing it through a pad of silica gel to give the title compound (8.03 g). LCMS m/z=260.2.

Provenance & Evidence