C1(C2ON=C(C3C=CN=CC=3)C=2)CC1.[CH:15]1([C:18]2[CH:22]=[C:21]([C:23]3[CH:28]=[CH:27][N:26]=[CH:25][CH:24]=3)[O:20][N:19]=2)[CH2:17][CH2:16]1.[H][H]>[Pt]=O.C(O)C>[NH2:19][C:18]([CH:15]1[CH2:17][CH2:16]1)=[CH:22][C:21]([C:23]1[CH:28]=[CH:27][N:26]=[CH:25][CH:24]=1)=[O:20]A 1.0 g. sample of the mixture of 4-(5-cyclopropyl-3-isoxazolyl)pyridine and 4-(3-cyclopropyl-5-isoxazolyl)pyridine, obtained as described in Examples 2 and 3, is mixed with 0.125 g. of platinum oxide and 75 ml. of ethanol. This mixture is treated with hydrogen on a Parr apparatus at 40 psi for 2 hours at room temperature. The mixture is filtered and the filtrate concentrated to yield a solid. Recrystallization from ethyl acetate-petroleum ether (30°-60°C.) provides 3-amino-3-cyclopropyl-1-(4-pyridyl)-2-propen-1-one as white crystals, melting point 124°-125°C. The ethyl acetate-petroleum ether (30°-60°C.) filtrate is concentrated to a solid which is recrystallized from aqueous ethanol to give 4-(5-cyclopropyl-3-isoxazolyl)pyridine as white crystals, melting point 78°-79.5°C., mmr spectrum δ6.85 (DMSO-d6, s, 4-isoxazolyl H).
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