Organic compounds -- part of the class 532-570 series – Organic compounds – Four or more ring nitrogens in the bicyclo ring system
Patent
1983-12-14
1986-01-28
Daus, Donald G.
Organic compounds -- part of the class 532-570 series
Organic compounds
Four or more ring nitrogens in the bicyclo ring system
C07D47514
Patent
active
045672628
ABSTRACT:
An improved process for the purification of crude riboflavin which has been prepared by condensation of an N-(D)-ribityl-2-arylazo-4,5-dimethylaniline and barbituric acid or another N-(D)-ribityl-4,5-dimethyl-aniline derivative with a barbituric acid derivative, by dissolving the crude riboflavin in sulfuric acid or phosphoric acid which has been diluted with water and oxidizing the impurities by treating the solution with hydrogen peroxide, or by dissolving the riboflavin in dilute nitric acid at elevated temperature and then isolating the pure riboflavin by precipitation with water, wherein the mineral acid solution of the riboflavin and the oxidizing agent or the solution of the riboflavin in 20 to 70% strength by weight nitric acid is heated extremely rapidly to a temperature at which the solution clearly changes color from greenish to yellow-orange, the solution is kept at this temperature for from 1 to 50, seconds and the oxidation reaction is then interrupted by addition of water.
The best results are achieved in this process if from 20 to 65% strength by weight nitric acid is used simultaneously as the acid and oxidative agent and if, after the change in color, the mineral acid solution, in particular the nitric acid solution, is passed, immediately or after prior interruption of the oxidation reaction by addition of cold water, into hot water at from 90.degree. to 100.degree. C. and the suspension thereby formed is kept at this temperature for about a further 10-30 minutes.
REFERENCES:
patent: 2324800 (1943-07-01), Pasternack et al.
patent: 2807611 (1957-09-01), Howe
Grimmer Johannes
Horn Hans C.
BASF - Aktiengesellschaft
Daus Donald G.
Rivers Diana G.
LandOfFree
Purification of riboflavin does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Purification of riboflavin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Purification of riboflavin will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1306940