2-Bromopropiophenone → 3,5-dimethyl-4-phenyl-3H-thiazole-2-thione

To a 100 mL flask was added freshly prepared triethylammonium methyldithiocarbamate (2.0 g, 9.5 mmol), anhydrous MeCN (50 mL), and 2-bromopropiophenone (2.04 g, 9.5 mmol). The reaction mixture was stirred at room temperature for 3 h. The reaction mixture was concentrated under reduced pressure and the resulting crude residue was treated with conc H2SO4 (5 mL) with stirring at room temperature. After 20 min, the reaction mixture was diluted with water (75 mL) and then mixed with DCM (75 mL). The layers were separated and the aqueous layer extracted once more with DCM (75 mL). The combined organic layers were washed with water (3×50 mL) and then brine (50 mL), dried over anhydrous MgSO4 and concentrated under reduced pressure to afford the title product (1.95 g, 92%) as an off-white solid, which was used without further purification. 1H-NMR (CDCl3): δ 7.50 (2H, m), 7.27 (2H, m), 3.45 (3H, s), 2.06 (3H, s).

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. additionthe resulting crude residue was treated with conc H2SO4 (5 mL)
3. stirringwith stirring at room temperature
4. waitAfter 20 min
5. additionthe reaction mixture was diluted with water (75 mL)
6. additionmixed with DCM (75 mL)
7. customThe layers were separated
8. extractionthe aqueous layer extracted once more with DCM (75 mL)
9. washThe combined organic layers were washed with water (3×50 mL)
10. dry with materialbrine (50 mL), dried over anhydrous MgSO4
11. concentrationconcentrated under reduced pressure

ORD record

ord-62cfb4e753d9434d8475a22330060c32

Source dataset

uspto-grants-2006_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07115640B2