1,1'-Carbonyldiimidazole → Hydroxy-bis-(3-methoxy-phenyl)-acetic acid (R)-(1-aza-bicyclo[2.2.2]oct-3-yl)ester

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Reaction Steps

To a stirred solution of hydroxy-bis-(3-methoxy-phenyl)-acetic acid (Intermediate J) (1.384 g, 4.8 mmol) in dry THF (2.0 ml) is added CDI (0.870 g, 5.3 mmol) and the mixture is heated to reflux for 90 minutes. (R)-1-aza-bicyclo[2.2.2]octan-3-ol (0.67 g, 5.3 mmol) is then added. After refluxing for 16 hours, the reaction mixture is diluted with ethyl acetate and washed with water. The organic layer is then extracted with 2M HCl and the aqueous portion is treated with potassium carbonate to basify the solution. The aqueous portion is re-extracted with ethyl acetate. The organic portions are combined, dried over MgSO4 and concentrated in vacuo to yield a crude residue which is purified using C-18 reverse phase column chromatography (eluent: water-acetonitrile), to afford the titled compound.

Provenance & Evidence