反应详情

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.

1. temperatureThe mixture is refluxed for 2 hours
2. customthe pyridine evaporated in vacuo
3. customThe residue is partitioned between ethyl acetate and 5% HCl
4. extractionThe ethyl acetate extract
5. washis washed with water
6. dry with materialdried over Na2SO4
7. customevaporated
8. customto give a pale yellow solid which
9. customfor approximately 13 minutes
10. customevaporated to dryness