Hydrochloric Acid → 5-Amino-3H-thiazolo[4,5]pyrimidine-2-one

Temperature

80 °C

5-Amino-3H-thiazolo[4,5-d]pyrimidin-2-thione (0.24 g, 1.3 mmol, 1.0 eq) was dissolved in 8 ml water containing 0.1 g NaOH (2.5 mmol, 2.5 eq). The resulting solution was heated to 80° C. A solution of sodium hypochlorite (NaClO) (4.4 ml, 10-13% solution, 5 eq) was added slowly to the above solution at about 80° C. and stirring was continued at 80-90° C. for 30 minutes. The solution was cooled down to about 70° C. and a concentrated HCl solution (0.3 ml, 37%, 2.3 eq.) was added, after which the resulting solution was heated to 80-90° C. for one hour. The reaction mixture was cooled down to room temperature and filtered through a pad of celite. The pH of the filtrate was adjusted to 5-5.5 using 10% NaOH solution. The resulting mixture was heated up to 60° C. for 1 hour, cooled to room temperature and stirred for at least two hours, filtered and washed with water and acetonitrile to afford 0.06 g (27%) of 5-amino-3H-thiazolo[4,5-d]pyrimidin-2-one as a pale yellow solid. 1H NMR, HPLC and LCMS analyses of this product are identical to the product described in Step 3 of Example 1.

1. temperatureThe solution was cooled down to about 70° C.
2. temperatureafter which the resulting solution was heated to 80-90° C. for one hour
3. temperatureThe reaction mixture was cooled down to room temperature
4. filtrationfiltered through a pad of celite
5. temperatureThe resulting mixture was heated up to 60° C. for 1 hour
6. temperaturecooled to room temperature
7. stirringstirred for at least two hours
8. filtrationfiltered
9. washwashed with water and acetonitrile

ORD record

ord-b9afe5777cae475eb147499115b395ee

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07781581B2