17743-04-3Relevant articles and documents
Method for synthesizing caffeine
-
Paragraph 0034-0035; 0039-0040; 0044-0045; 0051-0052, (2021/01/04)
The invention discloses a method for synthesizing caffeine, and relates to the technical field of preparation of heterocyclic compounds containing purine ring systems. The preparation method comprisesthe following steps: mixing cyanoacetic acid and acetic anhydride at 30-80 DEG C for reaction, adding a solvent and dimethylurea, cooling to room temperature after reflux reaction is finished, filtering, concentrating filtrate, combining solids to obtain dimethylacetamide, adding liquid caustic soda to adjust the pH to 8-11, and reacting at 80-100 DEG C to generate dimethyl 4AU; the method comprises the following steps: completely dissolving dimethyl 4AU in formic acid, adding sodium nitrite, reacting at room temperature, adding a catalyst, keeping the temperature at 30-70 DEG C, recovering the catalyst after the reaction is finished, and concentrating mother liquor to recover formic acid, thereby obtaining dimethyl FAU; adding water and liquid caustic soda into dimethyl FAU, and carryingout a ring-closure reaction to obtain theophylline sodium salt; the theophylline sodium salt is subjected to methylation reaction and refining to obtain caffeine. The method has the advantages of accessible raw materials, mild and controllable reaction conditions, fewer steps, high yield and greatly higher product quality, is simple to operate, and can easily implement industrial production.
Synthesis of 1,3-Dimethyl-4-amino-5-nitroso-2,6-pyrimidindione and its Derivatives
Shirsagar,Bhave
, p. 649 - 651 (2007/10/03)
-
