Reaktion #2868

Reaktionsgleichung

Sulfuryl chloride

3-thiophen-2-yl-pyridine

n-BuLi

methylene chloride

→

title product

Ausbeute 79.1%

5-Pyridin-3-yl-thiophene-2-sulfonyl choride

Ausbeute 79.1%

Lösungsmittel

—

hexanes

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeSO2 gas is bubbled through the solution for 30 min
2. 2
   workup.STIRRINGstirred overnight
3. 3
   EinengenThe solution is concentrated to dryness
4. 4
   workup.STIRRINGthe reaction mixture is stirred for 30 min
5. 5
   workup.STIRRINGthe mixture is stirred for another 30 min
6. 6
   EinengenThe mixture is then concentrated to dryness
7. 7
   workup.ADDITIONdiluted with ethyl acetate
8. 8
   Waschenwashed with saturated NaHCO3 (aq), water and brine
9. 9
   TrocknenThe organic layer is dried over MgSO4
10. 10
    Filtrationfiltered
11. 11
    Einengenconcentrated

Vorschrift

To a solution of 3-thiophen-2-yl-pyridine (0.355 g, 2.20 mmol) in 15 mL of THF at -78° C. is added n-BuLi (1.44 mL of a 1.6M solution in hexanes, 2.31 mmol). After stirring for 15 min, SO2 gas is bubbled through the solution for 30 min. The solution is then allowed to warm to room temperature and stirred overnight. The solution is concentrated to dryness and the resulting solid is suspended in 20 mL of hexane. Sulfuryl chloride (0.185 mL, 2.31 mmol) is added and the reaction mixture is stirred for 30 min then a small amount of methylene chloride is added and the mixture is stirred for another 30 min. The mixture is then concentrated to dryness and diluted with ethyl acetate and washed with saturated NaHCO3 (aq), water and brine. The organic layer is dried over MgSO4, filtered and concentrated to give a brown solid as the title product (0.452 g, 1.74 mmol) which is used in the subsequent step without further purification.

Quelle