Method for preparing optically pure R-1-naphthylethylamine by splitting

Abstract

The invention relates to a method for preparing optically-pure R-1-naphthylethylamine by splitting. The method comprises the following steps: introducing hydrogen into a high-pressure kettle filled with 1-naphthylethylamine serving as a raw material, Novozym435 serving as a splitting catalyst and D-(-)-O-acetyl mandelic acid serving as an acyl donor and KT-02 (nickel type catalyst) serving as a racemization catalyst for reacting, and fully transforming the 1-naphthylethylamine to obtain (R)-(1-(1-naphthyl)ethyl)acetamide (ee value is 99 percent); and purifying amide, performing acidolysis to obtain a R-1-naphthylethylamine salt, and performing the operation of alkalization, distillation, drying, concentration and the like on the R-1-naphthylethylamine salt to obtain the R-1-naphthylethylamine, wherein the product yield and the ee value in the whole steps can be over 90 percent. The method has the characteristics of adoption of cheap and readily-available racemization catalyst, complete utilization of the raw material, high product yield and the like. The method has extremely high guidance and application values in the production and preparation of the R-1-naphthylethylamine.

Description

technical field [0001] The invention relates to a resolution and preparation method of optically pure chiral amine, in particular to a resolution and preparation method of optically pure R-1-naphthylethylamine. Background technique [0002] Optically pure chiral amines are very important pharmaceutical intermediates. At present, optically pure chiral amines are mainly obtained through the following methods: enzymatic resolution (Indian J. Chem. Sect. B 2005, 44, 1312-1316; J. Org. Chem. 1997, 62, 3488-3495); Chemical resolution: resolution with chiral α-hydroxynaphthaleneacetic acid (US6342636; Tetrahedron: asymmetry, 1998, 9, 2219-2212) or protected chiral glycerol derivatives (Tetrahedron: asymmetry, 1996, 7, 1117-1122 ; Tetrahedron: asymmetry, 2002, 13, 2277-2282); obtained by asymmetric synthesis of the corresponding aldehyde (WO2004 / 110976; J. Org. Chem. 1992, 57, 1237-1241). [0003] Among the existing methods, the cost of asymmetric synthesis is high and it is often...

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Problems solved by technology

[0003] Among the existing methods, asymmetric synthesis is costly and often difficult to obtain products with high optical purity; chemical resolution and enzymatic kinetic resolution have the disadvantage of low raw material utilization, which is only 50% at most; In the reported enzymatic dynamic kinetic resolution method, the racemization catalysts used are usually complexes of some noble metals such as ruthenium and rhodium. These racemization catalysts are extremely expensive, and when these racemization catalysts are used in the resolution preparation process , although a high conversion rate is achieved, it is difficult to obtain a high optical purity of the product