24-12-2008 дата публикации
Номер: CN0101328173A
Автор:
LI RUIJIAN,
DONG PENG,
CUI CHUNXIA,
LI DONGLEI,
LI GUOCONG,
ZHENG XUEQING,
HAO XIAOYAN,
RUIJIAN LI,
PENG DONG,
CHUNXIA CUI,
DONGLEI LI,
GUOCONG LI,
XUEQING ZHENG,
XIAOYAN HAO
Принадлежит:
The invention relates to a method for preparing a hydrochloride of 6-Fluoro-3-(4-piperidinyl)-1,2-benzisoxazole. The method is to subject 2,4-difluorophenyl(4-piperidinyl) ketoxime or a hydrochloride thereof to cyclopropanation and salifying in an aprotic solvent containing an alkali metal hydroxdide, wherein the molar ratio of the 2,4-difluorophenyl(4-piperidinyl) ketoxime or a hydrochloride thereof to the alkali metal hydroxide is 1 to between 1 and 3. The method can effectively prevent F atoms on para positions from participating in the reaction and avoid the production of a dipolymer (V), thereby avoiding the production of a dipolymer (VI) during the following preparation of risperidone. The method crystallizes crystals of a target substance directly by salifying, thereby solving the problems of use of a plurality of kinds of organic solvents, complex operation and low yield due to the extraction by toluene, condensation, and crystallization of petroleum ether. The yield rate of the ...
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