To 2.47 g (9.3 mmol) of 2-benzenesulfonylmethyl-5-cyclopropyl-[1,3,4]oxadiazole in 25 mL of MeOH at 0° C., 170 μL (0.93 mmol, 0.1 eq) of a solution of sodium methoxyde (5.4 M in MeOH) were added. After 15 min, 895 mg (9.3 mmol, 1 eq) of cyclohex-2-enone were added. The reaction mixture was stirred from 0° C. to RT over 4 hours, diluted with saturated aqueous NH4Cl and extracted with EtOAc. The combined organic phases were dried over Na2SO4, filtered and evaporated. Column chromatography on silica gel with EtOAc/heptane 2:1 gave 1.48 g (44%) of 3-[benzenesulfonyl-(5-cyclopropyl-[1,3,4]oxadiazol-2-yl)-methyl]-cyclohexanone as a racemic mixture of diastereomers, white solid, MS: 361 (MH+).
