103146-25-4Relevant articles and documents
Synthesis method of citalopram intermediate
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, (2020/08/25)
The invention provides a preparation method of a citalopram intermediate 4-(4-(dimethylamino)-1-(4-fluorophenyl)-1-hydroxybutyl)-3-(hydroxymethyl) benzonitrile. The method provided by the invention has the advantages of cheap and easily available raw materials, short reaction steps, high yield, simple post-treatment, easy operation and the like, reduces the cost, has certain technical advantages,and is suitable for large-scale industrial production.
Preparation method of high-optical-purity escitalopram oxalate intermediate S-configuration diol
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Page/Page column 5-9, (2019/08/12)
The invention discloses a preparation method of an escitalopram oxalate intermediate S-configuration diol. The preparation method comprises the following steps: (1) carrying out hydrobromic acid salinization on racemic diol (4-(4-dimethylamino-1-p-fluorophenyl-1-hydroxybutyl)-3-(hydroxymethyl)benzonitrile) to obtain free racemic diol; and (2) carrying out chiral resolution on the free racemic diolby using (+)-di-p-toluoyl-D-tartaric acid in isopropanol by adopting a standing resolution mode, and conducting crystallization to obtain an escitalopram oxalate intermediate S-configuration diol crude product, and carrying out recrystallization refining on the crude product in an organic solvent to obtain the escitalopram oxalate intermediate with high optical purity. The method disclosed by theinvention is high in resolution efficiency and high in product yield, and the prepared diol intermediate is high in optical purity and can meet the requirements of industrial production.
Added-metal-free catalytic nucleophilic addition of Grignard reagents to ketones
Zong, Hua,Huang, Huayin,Liu, Junfeng,Bian, Guangling,Song, Ling
experimental part, p. 4645 - 4652 (2012/07/03)
On the basis of the investigation of the combinational effect of quaternary ammonium salts and organic bases, an added-metal-free catalytic system for nucleophilic addition reactions of a variety of Grignard reagents to diverse ketones in THF solvent has been developed to produce tertiary alcohols in good to excellent yields. By using tetrabutylammonium chloride (NBu4Cl) as a catalyst and diglyme (DGDE) as an additive, this system strongly enhances the efficiency of addition at the expense of enolization and reduction. NBu 4Cl should help to shift the Schlenk equilibrium of Grignard reagents to the side of dimeric Grignard reagents to favor the additions of Grignard reagents to ketones via a favored six-membered transition state to form the desired tertiary alcohols, and DGDE should increase the nucleophilic reactivities of Grignard reagents by coordination. This catalytic system has been applied in the efficient synthesis of Citalopram, an effective U.S. FDA-approved antidepressant, and a recyclable version of this catalytic synthesis has also been devised.