824430-78-6Relevant articles and documents
Method for preparing lorcaserin
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Paragraph 0035-0036; 0041, (2020/08/22)
The invention discloses a method for preparing lorcaserin. Specifically, the method comprises the steps: taking p-chlorophenylacetonitrile as an initial raw material, preparing p-chlorophenylethylamine through reduction; carrying out a reaction with p-toluenesulfonyl chloride to form an amino occupying intermediate; enabling the intermediate to carry out a reaction with monochloroacetone under analkaline condition to form N-(2-(4-chlorphenyl)ethyl)-4-methyl-N-(2-propionyl)benzenesulfonamide, and then carrying out reduction, chlorination, p-toluenesulfonyl removal and intramolecular Friedel-Crafts alkylation to synthesize 8-chloro-1-methyl-2,3,4,5-tetrahydro-1H-3-benzoazepine, carrying out L-(+)-tartaric acid resolution and alkalization on azepine to remove tartaric acid, and acting with hydrogen chloride diethyl ether to salify to prepare lorcaserin. The method has the characteristics of simple synthesis method, good reaction selectivity, high product purity, environmental protectionand low preparation cost.
Preparation method of lorcaserin intermediate
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, (2017/08/29)
The invention discloses a preparation method of a lorcaserin intermediate (I). According to the preparation method, p-chlorobenzyl cyanide is taken as the primary raw material, and the lorcaserin intermediate (I) is obtained after reduction reactions and condensation reactions. The primary raw materials (p-chlorobenzyl cyanide and 1-chloro-2-propanol) are cheap and easily available; raw materials, which can easily get polluted and are explosive, such as sulfoxide chloride, hydrobromic acid, borane, and the like are not used; the preparation method will not produce a large amount of wastewater and is beneficial for the environment protection; moreover, the requirements on the protection of workers are lowered, and safe production is guaranteed. The route design is novel, the raw materials are easily available, the operation is simple and feasible, and the preparation method is environment-friendly and can be applied to massive industrial production.
A preparing method of (R,S)-8-chloro-1-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine, a lorcaserin intermediate
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, (2016/10/17)
A preparing method of (R,S)-8-chloro-1-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine that is a lorcaserin intermediate is disclosed. The method includes (1) dehydrating a compound 1 and a compound 2 under catalysis by boric acid to generate an amide 3, (2) reducing the intermediate 3 with a borane dimethylsulfide complex to obtain a compound 4, and (3) subjecting the compound 4 to direct ring closing with the existence of aluminum chloride to generate the lorcaserin intermediate that is the (R,S)-8-chloro-1-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine that is the compound 6. The method avoids use of 3,4,5-trimethoxyphenylboronic acid that is an expensive reagent, thus reducing the cost. The method avoids use of thionyl chloride so that the method is environmental friendly. A step of hydroxy chlorination is reduced so that the method is simple in process. The conversion ratio of raw materials and the total yield of reactions are increased. The yield of the compound 6 is increased from 60% in a patent to 82%. The method is suitable for industrial production. A reaction equation is shown in the description.