[F:1][C@@H:2]1[CH2:4][C@H:3]1[C:5]([OH:7])=O.C(N1C=CN=C1)(N1C=CN=C1)=O.O[N:21]=[C:22]([NH2:33])[C:23]1[CH:28]=[CH:27][C:26]([CH3:29])=[C:25]([N+:30]([O-:32])=[O:31])[CH:24]=1>CN1C(=O)CCC1>[F:1][CH:2]1[CH2:4][CH:3]1[C:5]1[O:7][N:33]=[C:22]([C:23]2[CH:28]=[CH:27][C:26]([CH3:29])=[C:25]([N+:30]([O-:32])=[O:31])[CH:24]=2)[N:21]=1To a stirring solution of trans-2-Fluoro-cyclopropanecarboxylic acid (0.38 g, 3.68 mmol) in anhydrous NMP (12 mL) was added 1,1′-carbonyldiimidazole (CDI) (0.59 g, 3.68 mmol). The reaction was stirred for 3 minutes. N′-hydroxy-4-methyl-3-nitrobenzimidamide (27) (0.72 g, 3.68 mmol) was added and the reaction was stirred for minutes then heated in the microwave at 120° C. for 15 minutes. The crude product was extracted with ethyl acetate. The organic layer was washed with water, brine and dried over anhydrous sodium sulfate. The solvent was concentrated and the crude product was purified on silica gel using ethyl acetate and hexane to yield 5-(2-fluorocyclopropyl)-3-(4-methyl-3-nitrophenyl)-1,2,4-oxadiazole (129). MS m/z 264.1 (M+1)+.
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