Water → (2S)-2-Cyclopentyl-2-hydroxy-2-thien-2-ylacetic Acid (3S)-1-azabicyclo[2.2.2]oct-3-yl ester

Participants

Reaction Steps

510 mg (0.00225 mol) of (2S)-2-Cyclopentyl-2-hydroxy-2-thien-2-ylacetic acid (obtained by hydrolysis of Intermediate I-15a) were dissolved in 7 ml of DMF. This solution was stirred at room temperature and 638 mg (0.00393 mol) of 1,1′-carbonyldiimidazol were added in several portions. After 4.5 h the reaction mixture was cooled to 0° C. and 315 mg (0.00248 mol) of (3S)-3-hydroxy-1-azabicyclo[2.2.2]octane and 83 mg (0.0021 mol) of HNa (60% dispersion in mineral oil) were added thereto. After stirring 112 h at room temperature the reaction mixture was treated with water and extracted three times with diethyl ether. The organic layers were combined, washed with brine and dried over anhydrous magnesium sulfate. The solvent was evaporated and the residue was purified by silica gel column chromatography (eluent CHCl6/MeOH 15:1) to obtain 360 mg (47.6%) of the title product as an oil, structure confirmed by 1H-RMN.

Provenance & Evidence