Pyridine → 2-bromoethyl trifluoromethanesulfonate

Temperature

-20 °C

Anhydrous pyridine (8.5 mL, 105 mmol) and dry DCM (100 mL) were added to a 3-necked round-bottomed flask under a nitrogen atmosphere. The reaction flask was then cooled to about −20° C. with a dry ice/ethylene glycol bath. Trifluoromethanesulfonic anhydride (17 mL, 100 mmol) was added, whereupon a white/pink precipitate formed immediately. 2-Bromoethanol (7.1 mL, 100 mmol) was added after 5 minutes. The precipitate disappeared and then after a few minutes a new white precipitate formed. The reaction mixture was stirred for 20 minutes during which time it gradually warmed to r.t. The reaction mixture was then filtered through a phase separator and the residue was washed with 1:1 DCM/hexane (2×10 mL). The filtrate was run through a 4 cm silica plug with 1:1 DCM/hexane solution (300 mL). The solvent was removed in vacuo to give the title compound as a brown oil (21.2 g, 87%). δH (CDCl3) 4.76 (2H, t, J 6.4 Hz), 3.62 (2H, t, J 6.4 Hz).

1. customformed immediately
2. customafter a few minutes a new white precipitate formed
3. temperaturegradually warmed to r.t
4. filtrationThe reaction mixture was then filtered through a phase separator
5. washthe residue was washed with 1:1 DCM/hexane (2×10 mL)
6. customThe solvent was removed in vacuo

ORD record

ord-a7aa1786eeb94ef78a070814bb2b55df

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08637491B2