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:
Mar. 19, 2013
Filed:
Mar. 09, 2009
Pradeep Kumar Gupta, Gwalior, IN;
Laxmi Manral, New Delhi, IN;
Kumaran Ganesan, Gwalior, IN;
Ramesh Chandra Malhotra, Gwalior, IN;
Krishnamurthy Sekhar, New Delhi, IN;
Pradeep Kumar Gupta, Gwalior, IN;
Laxmi Manral, New Delhi, IN;
Kumaran Ganesan, Gwalior, IN;
Ramesh Chandra Malhotra, Gwalior, IN;
Krishnamurthy Sekhar, New Delhi, IN;
Defence Research & Development Organisation, Bhawan, IN;
Abstract
The invention provides a method for the preparation of fentanyl comprising: (a) reacting 4-piperidone hydrochloride monohydrate with aniline in presence of reducing environment to produce 4-anilinopiperidine (4-AP), (b) reacting the 4-AP as obtained from step (a) with phenethyl halide under reflux conditions in highly alkaline medium to give 4-anilino-N-phenethylpiperidine, and (c) converting the 4-anilino-N-phenethylpiperidine to fentanyl by reacting with propionyl chloride in presence of halogenated hydrocarbons, then isolating fentanyl by solvent extraction and purifying by crystallization from petroleum ether at a temperature ranging from 60-80° C.