Preparation of codeine from morphine
Patent 6579985 Issued on June 17, 2003. Estimated Expiration Date: 
October 21, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
October 21, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesProcess for the preparation of codeine from morphine Solid-phase synthesis of codeine from morphine Patent #: 6204337 InventorApplicationNo. 274702 filed on 10/21/2002US Classes:546/44One of the five cyclos is five-membered and includes ring chalcogen (e.g., codeine, morphine, etc.)ExaminersPrimary: Morris, Patricia L.International ClassC07D 489/02AbstractAn improved process for the preparation of codeine from morphine comprises the steps of a) reacting morphine with a methylating agent in the presence of a hydrocarbon solvent at a temperature of 100 to 215° C. under reflux conditions such that approximately 50% or more of the hydrocarbon solvent is returned to the reaction mixture to substantially avoid the formation of codeine methyl ether; and b) recovering codeine from the reaction mixture. The process may include step a) above followed by b) cooling the reaction mixture to approximately 85° C. and adding water to terminate the reaction; c) raising the pH of the reaction mixture to approximately 11; d) separating the hydrocarbon solvent phase containing codeine and dimethylaniline; and e) adding a dilute mineral or organic acid and approximately 6 to 7 times the volume of water for each volume of hydrocarbon solvent to separate dimethylaniline and codeine. |
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