1,1'-Carbonyldiimidazole → 3-(((3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-methyl-2-oxo-1-(pentan-3-yl)piperidin-3-yl)methyl)-1,2,4-oxadiazol-5(4H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 385 mg (0.81 mmol) of 2-((3R,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-3-methyl-2-oxo-1-(pentan-3-yl)piperidin-3-yl)-N′-hydroxyacetimidamide (Example 82, Step C) in dioxane (12.5 mL) was added 211 μL (1.41 mmol) of DBU and 262 mg (1.62 mmol) of 1,1′-carbonyldiimidazole. The resulting colorless solution was heated at 100° C. for 25 min, and then was quenched with water and extracted with EtOAc. The organic layer was washed with saturated aqueous sodium chloride, and then was 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 55% MeCN in water to 80% MeCN in water over a 35 min period, where both solvents contain 0.1% TFA) provided the title compound as a white solid.

Provenance & Evidence