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:
Apr. 16, 2013
Filed:
Jan. 30, 2009
Alessandro Leganza, Alte Di Montecchio Maggiore, IT;
Marco Galvagni, Alte Di Montecchio Maggiore, IT;
Alessandro Leganza, Alte Di Montecchio Maggiore, IT;
Marco Galvagni, Alte Di Montecchio Maggiore, IT;
F.I.S. Fabbrica Italiana Sintetici S.p.A., Alte di Montecchio Maggiore, IT;
Abstract
The present invention is directed to a process for the preparation of Efavirenz, (4S)-6-chloro-4-(cyclopropylethynyl)-4-(trifluoromethyl)-1,4-dihydro-2H-3,1-benzoxazin-2-one, of formula (I) comprising reacting the intermediate of formula (II) [0045] as a free base or a salt thereof, with diphosgene (TCMCF, trichlormethylchloroformate) Cl3CO—COCl in an organic solvent or in a biphasic medium comprised of an organic solvent and water, preferably but not mandatorily in the presence of a weak base in an amount sufficient to neutralise the reaction mixture or in an up to 30% molar excess of such amount.