113806-02-3Relevant articles and documents
Preparation method of E-olopatadine
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Paragraph 0016; 0040; 0043, (2021/03/11)
The invention discloses a preparation method of E-olopatadine, which comprises the following steps: adding [3-(dimethylamino)propyl]triphenylphosphine bromide hydrobromide into a solvent, adding an n-pentane solution of tert-butyl lithium, carrying out heat preservation reaction for 0.5-2 hour, heating to 105-110 DEG C, dropwise adding a toluene solution of methyl 6, 11-dihydro-11-oxo-dibenzo(b, e)oxepine-2-acetate, heating to 105-110 DEG C, stirring for 2-5 hours at the temperature of 105-110 DEG C, then cooling to 0-15 DEG C, carrying out quenching reaction, adding concentrated hydrochloricacid to adjust the pH value to 6+/-0.2, carrying out reduced pressure distillation to dryness to obtain a solid, enabling the solid to pass through a column to obtain an E-olopatadine methyl ester crude product, and carrying out purification. According to the preparation method of Eolopatadine provided by the invention, on the basis of the prior art, key steps are upgraded and transformed, so thatthe reaction steps can be reduced, and the loss is reduced.
