[NH2:1][C:2]1[N:6]2[C:7]([O:13][CH3:14])=[N:8][CH:9]=[C:10]([O:11][CH3:12])[C:5]2=[N:4][N:3]=1.C[O-].[Na+]>CO.O>[NH2:1][C:2]1[N:6]=[C:5]2[N:4]([C:7]([O:13][CH3:14])=[N:8][CH:9]=[C:10]2[O:11][CH3:12])[N:3]=13-Amino-5,8-dimethoxy[1,2,4]triazolo[4,3-c]-pyrimidine (9.762 g, 0.050 mole) was loaded into a 500 mL three necked flask equipped with an overhead stirrer, condenser, addition funnel, and thermocouple temperature probe. Methanol (70 mL) was added and the mixture was stirred to form a slurry. Sodium methoxide (16.716 g of a 25% solution in methanol) was added dropwise over 28 min, after which the mixture was stirred at room temperature for 3 h. The reaction mixture was then diluted with water (135 mL) and stirred for an additional 1.5 h. The product solids were recovered by filtration through Whatman #54 paper using a Buchner funnel and aspirator vacuum. After washing with water, the solids were dried in vacuo at room temperature to give 9.064 g of 2-amino-5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidine (yield=92.8%): 1H NMR (300 MHz, DMSO-d6) 3.88 (s, 3H), 4.04 (s, 3H), 6.38 (br s, 2H), 7.48 (s, 1H); MS(GC, 70eV) 195 (M+, 85%), 194 (100%)
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