Hydrochloric Acid → HCID 178435040, compound

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Reaction Conditions

Reaction Steps

To a solution of 4-amino-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-one (Example 165a) (1082 g, 5.54 moles) in water (8.1 L) was added an ethanolic solution of HCl (1.25 N in 200 proof ethanol). The resulting slurry was heated to reflux for 15 minutes to afford a clear solution. (In some cases additional 1:1H2O:1.25 N HCl in ethanol must be added to obtain a clear solution). The solution was filtered while hot and the filtrate cooled to 0° C. while stirring. The resulting precipitate was collected by filtration, and washed with acetone (3×5.4 L) and heptane (3×5.4 L). The solids were placed in drying trays and dried under vacuum overnight to give 4-amino-5,6-dimethylthieno[2,3-d]pyrimidine-2(1H)-one hydrochloride as an off white powder (1176 g, 92% yield). >99% pure as determined by HPLC. M.p.: >260° C. 1H NMR (400 MHz, DMSO-d6) δ 2.30 (s, 6H), 8.56 (bs, 1H), 9.54 (bs, 1H), 12.92 (bs, 2H). 13C NMR (400 MHz, DMSO-d6) δ 12.2, 13.3, 106.5, 125.5, 125.7, 146.1, 154.9, 155.3. MS 196.2 (MH+). Purity as determined by HPLC, 99.64%.

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