934971-01-4Relevant academic research and scientific papers
A (2 R, 3 S) - 1 - chloro - 3 - tert-butoxy amide - 4 - phenyl - 2 - butanol preparation method
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, (2017/09/26)
The invention provides a preparation method for (2R,3S)-1-chlorine-3-tert-butoxycarbonylamino-4-phenyl-2-butanol. The preparation method comprises the steps that L-phenylalanine is taken as raw materials, protected by adopting benzyl, esterified and then catalyzed through NMM to generate a mixed anhydride compound, the mixed anhydride compound reacts with diazomethane to generate diazoketone, a reduction reaction and palladium carbon reduction are performed, and finally the intermediate (2R,3S)-1-chlorine-3-tert-butoxycarbonylamino-4-phenyl-2-butanol is obtained. According to the preparation method, the low-cost benzyl is adopted to protect amidogen, the synthetic route is reasonable, the operation technology is simple, safe and high in yield, industrialization can be well achieved, and the production efficiency is improved.
Production method of aminochlorohydrin sulfate
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Page/Page column 18-19, (2010/11/26)
Highly pure (2R,3S)-3-tert-butoxycarbonylamino-1-chloro-2-hydroxy-4-phenylbutane or (2S,3R)-3-tert-butoxycarbonylamino-1-chloro-2-hydroxy-4-phenylbutane may be conveniently produced in high yield by: (a) reacting compound (1) with lithiumchloromethane to give compound (2) and at least a byproduct; (b) dissolving compound (2) and the byproduct in a polar solvent and adding water to the solution to precipitate compound (2) as crystals; (c) reducing the crystals of compound (2) to give compound (3) and at least its diastereomer as an impurity; (d) adding sulfuric acid thereto to give compound (4) and at least its diastereomer as an impurity; and (e) precipitating compound (4) as crystals from a solution containing acetic acid ester or acetic acid ester.
