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:
Aug. 14, 2007
Filed:
Mar. 21, 2003
Vuddamari Srinivas Goud, Karnataka, IN;
Santosh Laxman Gaonkar, Mysore Karnataka, IN;
Saji Thomas, Karnataka, IN;
Sulur G Manjunatha, Karnataka, IN;
Ashok Krishna Kulkarni, Karnataka, IN;
Ambati Narahari Babu, Karnataka, IN;
Vuddamari Srinivas Goud, Karnataka, IN;
Santosh Laxman Gaonkar, Mysore Karnataka, IN;
Saji Thomas, Karnataka, IN;
Sulur G Manjunatha, Karnataka, IN;
Ashok Krishna Kulkarni, Karnataka, IN;
Ambati Narahari Babu, Karnataka, IN;
Jubilant Organosys Limited, , IN;
Abstract
A method is provided for the isolation of high purity crystalline citalopram (1-[3-dimethylamino)propyl}-1-(4-fluorophenyl)-1, 3-dihydro-5-isobenzofurancarbonitrile) base directly from the alkylation reaction mixture of 5-cyanophthalane with N,N-dimethylaminoprpylchloride in a polar aprotic solvent using a strong base. The method comprises: (a) diluting the reaction mixture with ice cold water and extracting the resulting mixture with a water-immiscible organic solvent; (b) re-extracting the water-immiscible organic solvent extract with an aqueous acid; (c) diluting the aqueous acid extract with a substantially equal volume of a water miscible organic solvent, based on the volume of water in the aqueous acid extract; (d) adjusting the pH to basic with an inorganic base to precipitate free crystalline base and (e) further isolating the precipitated free crystalline base by filration.