The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 03, 2020
Filed:
Nov. 23, 2017
Siegfried (Nantong) Pharmaceuticals Co. Ltd., Nantong Jiangsu, CN;
Siegfried (Nantong) Pharmaceuticals Co. Ltd., Nantong Jiangsu, CN;
Abstract
The current invention offers a process for the production of N-Boc-2-amino-3,3-dimethylbutyric acid by a reaction of tert-Leucine with di-tert-butyl-dicarbonate, the process comprising (i) contacting the tert-Leucine with di-tert-butyl-dicarbonate in an aqueous medium, optionally comprising a first organic solvent, in the presence of an inorganic base, (ii) optionally removing the first organic solvent, (iii) optionally extracting the resulting N-Boc-2-amino-3,3-dimethylbutyric acid into a second organic solvent, (iv) isolating the product by precipitation from the reaction mixture at acidic pH, and (v) optionally reuse the first and/or second organic solvents recovered from step (ii) and/or step (iv) for the next production cycle. The process is sufficiently short, uses preferably environmental friendly solvents, avoids waste and leads to good yields.