Electric Literature of 369638-68-6, A common heterocyclic compound, 369638-68-6, name is tert-Butyl (5-methylpyrazin-2-yl)carbamate, molecular formula is C10H15N3O2, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
5-Methylpyrazin-2-amine To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added tert-butyl (5-methylpyrazin-2-yl)carbamate (1.0 eq), and water (6.85 vols). The mixture was heated to 70 C. and trifluoroacetic acid (TFA) (1.2 eq) was added slowly drop-wise over 90-120 minutes. Water (0.22 vols) was added to wash the TFA into the flask. The reaction mixture was heated at 65-75 C. for at least 30 minutes, and then cooled to 15-25 C. Then 32% w/w sodium hydroxide (1.30 eq) was added drop-wise over 30-60 minutes maintaining the reaction temperature between 15-40 C. Water (0.22 vols) was added to wash the sodium hydroxide into the flask. N-Propylacetate (7.0 vols) was added and the mixture agitated for 45 minutes at 20 C. The layers were separated, the organic layer was retained and the aqueous layer was returned to the flask. N-Propylacetate (7.0 vols) was added and the mixture agitated for 45 minutes at 20 C. The layers were separated, the organic layer was retained and the aqueous layer was returned to the flask. This process was repeated twice. The combined organic layers were filtered through a filter containing silica (20% w/w) into a clean dry flask. The mixture was heated to 40 C. and then vacuum distilled to a final volume of 1.0-1.33 vols. Toluene (3.0 vols) was added, and the vacuum distillation continued at 40 C. to a final volume of 1.0-1.33 vols. This process was repeated twice. The resulting mixture was cooled to 5 C., and agitated for 1 hour at this temperature then filtered, washed with toluene (0.3 vols) at 0-5 C. The batch is slurry washed with toluene (1.0 vol) at 0-5 C. After drying at 45 C. overnight, the desired product was obtained as a solid (corrected yield typically 75%). 1H NMR delta (400 MHz CDCl3): 7.92 (s, 1H), 7.87 (s, 1H), 4.6 (bs, 2H), 2.40 (s, 3H)
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; AstraZeneca AB; US2010/210621; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem