2,4-Dichloro-5-(trifluoromethyl)pyrimidine → 4-Chloro-2-(methylthio)-5-(trifluoromethyl)pyrimidine

To a solution of the 2,4-dichloro-5-(trifluoromethyl)pyrimidine (2.50 g, 11.5 mmol) in THF (50 mL) in an ice bath under nitrogen was added zinc(II) chloride (1.0 M in ether, 13.8 mL, 13.8 mmol) dropwise. The mixture was stirred in the ice bath for two hours, then sodium methanethiolate (0.888 g, 12.7 mmol) was added. The mixture was stirred overnight, allowing the reaction to slowly come to room temperature. After 18 hours the reaction was quenched with 2 M HCl (15 mL), and the organics removed by evaporation under reduced pressure. The aqueous residue was diluted with brine (15 mL), and extracted with DCM (3×30 mL). The combined organic phases were dried (phase separator) and carefully evaporated to give a pale yellow oil. Chromatography (2×40 g silica cartridge, 0-20% DCM/n-hexane) followed by carefully evaporation of solvent (40° C.@400 mmHg then room temperature@200 mmHg) gave the title compound (I11) (2.149 g, 82% yield) as a colourless oil; 1H NMR (600 MHz, CDCl3) δ 8.66 (s, 1H), 2.61 (s, 3H). LCMS Method C: rt: 7.95 min; m/z 229.1 [M+H]+, Note: I11 is volatile.

1. customthe reaction
2. customto slowly come to room temperature
3. customAfter 18 hours the reaction was quenched with 2 M HCl (15 mL)
4. customthe organics removed by evaporation under reduced pressure
5. additionThe aqueous residue was diluted with brine (15 mL)
6. extractionextracted with DCM (3×30 mL)
7. customThe combined organic phases were dried (phase separator)
8. customcarefully evaporated
9. customto give a pale yellow oil
10. customChromatography (2×40 g silica cartridge, 0-20% DCM/n-hexane) followed by carefully evaporation of solvent (40° C.@400 mmHg

ORD record

ord-d11cee66d61b4fbcb30efe52189361f0

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09174946B2