Citric Acid → 2-((3R,5R,6S)-5-(3-Chlorophenyl)-6-(4-chlorophenyl)-1-((3S)-4-hydroxyhexan-3-yl)-3-methyl-2-oxopiperidin-3-yl)acetic acid

Participants

Reaction Steps

To a solution of 2-((3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-methyl-2-oxo-1-((S)-4-oxohexan-3-yl)piperidin-3-yl)acetic acid (0.038 g, 0.077 mmol; Example 158, Step B) in a mixture of THF and methanol (4:1, 5 mL) was added sodium borohydride (9 mg, 0.24 mmol) at 0° C. Then the reaction was allowed to warm to room temperature. After being stirred at room temperature for 1.5 h, another 2 eq. of sodium borohydride were added and stirred for another 0.5 h. The reaction was acidified (10% citric acid) and extracted (2×EtOAc). The combined organic layers were washed (sat. aq. NaCl solution), dried (MgSO4), and concentrated under reduced pressure. The crude material was purified by reverse phase preparatory HPLC (eluent: 10 to 90% acetonitrile, water, 0.1% TFA, gradient elution) to give the title compound as the first eluting fraction as a white solid after lyophilization.

Provenance & Evidence