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:
Feb. 21, 2017
Filed:
Dec. 04, 2015
Ampac Fine Chemicals Llc, Rancho Cordova, CA (US);
Aslam Malik, Cameron Park, CA (US);
Francis Hempenstall, Folsom, CA (US);
Nicholas Duda, Orangevale, CA (US);
Ali Suleman, Folsom, CA (US);
AMPAC Fine Chemicals LLC, Rancho Cordova, CA (US);
Abstract
Novel methods and systems for producing a substantially pure d-threo stereoisomer of methylphenidate or a salt thereof are provided. In particular, methods and systems for producing d-threo-methylphenidate hydrochloride in pure stereoisomeric form from d-threo-ritalinic acid hydrochloride using diazomethane are described. The described methods can be performed on a large scale, and thus provide d-threo methylphenidate or a salt thereof, and particularly the hydrochloride salt of d-threo-methylphenidate, in stereoisomerically pure form and in large quantities from a single batch reaction. Also described are novel compositions of d-threo methylphenidate hydrochloride.