Sulfuryl chloride → 5-(6-Methoxy-pyridin-3-yl)-4-methyl-thiophene-2-sulfonyl chloride

Temperature

-70 °C

2-Methoxy-5-(3-methyl-thiophen-2-yl)-pyridine (0.32 g, 1.6 mmol) was dissolved in THF/diethyl ether (10 ml, 1:1 v/v) and cooled to −70° C. BuLi (1.6M hexanes, 1 ml, 1.6 ml) was added dropwise and after a further 15 min at −70° C. the reaction mixture was added via canula to a condensed solution of SO2 (5 ml) in diethyl ether (10 ml). The yellow colored reaction mixture was slowly warmed to room temperature and stirred overnight. The reaction mixture was concentrated under reduced pressure and the residue washed with diethyl ether and dried. The crude solid (0.31 g) was suspended in dry n-hexane (7 ml), cooled using an ice bath to 0° C. and treated with a solution of sulfuryl chloride (1 M, 1.2 ml, 1.2 mmol) in CH2Cl2. The reaction mixture was slowly warmed to room temperature and analyzed (TLC) showing no starting material. Solvent was removed under reduced pressure and the crude product was purified over silica gel (n-heptane/tert.butylmethyl ether 1:9 to 1:4 v/v) to yield a white solid: 0.19 g (38%), MS: m/e 304.0 (MH+).

1. temperatureThe yellow colored reaction mixture was slowly warmed to room temperature
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. washthe residue washed with diethyl ether
4. customdried
5. temperaturecooled
6. customto 0° C.
7. temperatureThe reaction mixture was slowly warmed to room temperature
8. customSolvent was removed under reduced pressure
9. customthe crude product was purified over silica gel (n-heptane/tert.butylmethyl ether 1:9 to 1:4 v/v)
10. customto yield a white solid

ORD record

ord-658789fe53894ce0bb445e0f1fc72f39

Source dataset

uspto-grants-2011_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07868030B2