[H-].C([Al+]CC(C)C)C(C)C.C1(C)C=CC=CC=1.C[O:19][C:20]([C:22]1[C:23]([C:30]2[C:35]([Cl:36])=[CH:34][CH:33]=[CH:32][C:31]=2[Cl:37])=[N:24][O:25][C:26]=1[CH:27]1[CH2:29][CH2:28]1)=O.CO>C1COCC1.CCOC(C)=O.O>[CH:27]1([C:26]2[O:25][N:24]=[C:23]([C:30]3[C:31]([Cl:37])=[CH:32][CH:33]=[CH:34][C:35]=3[Cl:36])[C:22]=2[CH2:20][OH:19])[CH2:29][CH2:28]1Diisobutylaluminium hydride 1M/toluene (4.62 L, 4.62 mol) is added dropwise to a stirred solution of 5-Cyclopropyl-3-(2,6-dichloro-phenyl)-isoxazole-4-carboxylic acid methyl ester (687.14 g, 2.20 mol) in THF (4.4 L) at 0° C. The reaction is stirred at room temperature for 2 hours. Methanol (150 mL) is added over the mixture at 0° C. and stirred for 10 min. Then, water (2.2 L) and EtOAc (4.3 L) is added. The precipitate formed is filtered through celite and all the solvents are removed in vacuum. The solid is triturated in 1 L of hexane and dried under vacuum filtration to obtain title compound (534.7 g, 85% yield) as a white solid. MS (m/e): 312 (M+1).
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