Tempo → 3-((3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-methyl-2-oxo-1-(pentan-3-yl)piperidin-3-yl)-2-hydroxypropanoic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 142 mg (0.30 mmol) of (3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-(2,3-dihydroxypropyl)-3-methyl-1-(pentan-3-yl)piperidin-2-one (Example 81, Step A) and 28 mg (0.18 mmol) of TEMPO in a mixture of acetonitrile (6 mL) and sodium phosphate-sodium hydroxide buffer (pH 6.7, 4.5 mL) at 35° C. was treated simultaneously with a solution of 105 mg (1.16 mmol) of sodium chlorite in water (1.2 mL) and a solution of 106 μL (0.07 mmol) of bleach solution (ca. 0.7 N) in water (0.6 mL) over 10 min. The resulting dark orange solution was stirred at 35° C. for 1.75 h, and then was partitioned between 1 N HCl and EtOAc (3×). The combined organic layers were dried over Na2SO4, filtered and the filtrate was concentrated. Purification of the residue by reversed phase prep. HPLC (Sunfire™ Prep C18 OBD 10 μm column (Waters, Milford, Mass.), gradient elution of 60% MeCN in water to 80% MeCN in water over a 30 min period, where both solvents contain 0.1% TFA) provided the title compound (mixture of alcohol epimers) as a white solid.

Provenance & Evidence