| 摘要 |
FIELD: organic chemistry and technology. SUBSTANCE: invention relates to a method of optical purification of benzimidazole derivatives of the formulas (Ia) <EMI ID=0.1 HE=37 WI=63 TI=CHI>, (Ib) <EMI ID=0.2 HE=37 WI=45 TI=CHI>, (Ic) <EMI ID=0.3 HE=37 WI=45 TI=CHI>, (Id) <EMI ID=0.4 HE=37 WI=45 TI=CHI>, (Ie) <EMI ID=0.5 HE=30 WI=53 TI=CHI>. Method involves treatment of enantiomer-enriched preparation of any compound of the formulas (Ia-Ie) to obtain (+)- or (-)-enantiomer with a solvent followed by selective precipitation of racemate of the above indicated compounds. Precipitated racemate is filtered off, a solvent is removed and a single enantiomer of improved optical purity is obtained. Method does not require treatment of compounds (Ia-Ie) with reagents. EFFECT: simplified method, improved optical purity. 19 cl, 16 ex
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