[Cl:1][C:2]1[C:3]([OH:20])=[C:4]([CH:15]=[CH:16][C:17]=1[O:18][CH3:19])[C:5]([C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([F:13])[C:8]=1[F:14])=O.Cl.[NH2:22][OH:23]>N1C=CC=CC=1.C(OC(=O)C)C>[Cl:1][C:2]1[C:3]([OH:20])=[C:4]([CH:15]=[CH:16][C:17]=1[O:18][CH3:19])/[C:5](=[N:22]\[OH:23])/[C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([F:13])[C:8]=1[F:14]To a solution of 24 g of 3-chloro-2-hydroxy-4-methoxy-2',3'-difluorobenzophenone in 160 ml pyridine, 22 g of hydroxylamine HCl is added. The mixture is refluxed for 2 hours and the pyridine evaporated in vacuo. The residue is partitioned between ethyl acetate and 5% HCl. The ethyl acetate extract is washed with water, dried over Na2SO4 and evaporated to give a pale yellow solid which consists of two isomers. The solid is melted at 205° C. for approximately 13 minutes. The residue is dissolved in hot ethylacetate and then evaporated to dryness giving E-3-chloro-2',3'-difluoro-2-hydroxy-4-methoxybenzophenone oxime, mp 198°-199° C.
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