Acetic Acid → HCID 135974971, compound

Participants

Reaction Steps

To a solution of compound 19 (6.5 g, 11.57 mmol) in dry dichloromethane (100 mL) was added triethylamine (9.68 mL, 69.42 mmol) and cyclopentylacetic acid (4.35 mL, 34.71 mmol). The resultant solution was stirred at rt for 5 min. (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP, 15.36 g, 34.71 mmol) was added into the above solution in portions. The final mixture was stirred at rt overnight. The solvent was removed with rotavapor. To the residua was added THF (60 mL) and methanol (60 mL). A suspension of lithium hydroxide monohydrate (5.0 g, 119.2 mmol) in water (30 mL) was slowly added to the above solution. The mixture was stirred at rt for 1.5 hours and then neutralized with acetic acid (7.0 mL, 122.3 mmol). The mixture was diluted with ethyl acetate (˜300 mL), and washed with brine, and dried over sodium sulfate. It was filtered, concentrated and purified with silica column chromatography eluting with dichloromethane-ethyl acetate (v/v 9/1). After crystallizing with hexanes/ethyl acetate, the title compound (20, 5.1 g) was obtained as white solid in 65.6% yield.

Provenance & Evidence