Acetic Acid → [1,3]Thiazolo[4,5-b]pyrazine-2(3H)-thione

Temperature

150 °C

To a mixture of 2-amino-3-chloropyrazine (5 g, 38.6 mmol) and potassium ethyl xanthate (9.28 g, 57.9 mmol) was added 1-methyl-2-pyrrolidinone (68 mL) and the solution was heated (150° C., 16 h). The suspension was cooled (rt) and treated with glacial acetic acid (10 mL) and H2O (1500 mL). The suspension was filtered and the resulting solid was suspended and sonicated in ethanol:H2O (1:1, 500 mL). The suspension was filtered and the solid was washed with H2O, dried (calcium sulfate) in vacuo to yield the title compound as a solid (4.36 g, 67%). MS (ESI): mass calculated for C5H3N3S2, 168.98; m/z found, 170.00 [M+H]+. 1H NMR (500 MHz, DMSO-d6): 14.69 (s, 1H), 8.42 (d, J=2.8, 1H), 8.39 (d, J=2.8, 1H).

1. temperatureThe suspension was cooled (rt)
2. filtrationThe suspension was filtered
3. customsonicated in ethanol:H2O (1:1, 500 mL)
4. filtrationThe suspension was filtered
5. washthe solid was washed with H2O
6. dry with materialdried (calcium sulfate) in vacuo

ORD record

ord-7559fb1e5af0497faeaf29f400b18f81

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08399465B2