| abstract |
An improved process for preparing riboflavin 5'-phosphate (FMN) or its monosodium salt by reacting riboflavin with excess phosphorus oxychloride in a solvent, hydrolyzing of the resulting reaction mixture and, if desired, partially neutralizing with aqueous sodium hydroxide solution, comprises reacting the riboflavin with from 1.2 to 3 moles of phosphorus oxychloride per mole of riboflavin in a suitable lactone, especially gamma -butyrolactone, as solvent. The process is particularly advantageous when the reaction mixture is hydrolyzed at from 80 DEG to 90 DEG C. continuously or batchwise. |