Triethylamine → 3-Bromo-5-(bromomethyl)pyridine

Temperature

0 °C

(5-Bromopyridin-3-yl)methanol (1.41 g; 7.5 mmol) is dissolved in 20 mL DCM and the flask is flushed with argon and cooled to 0° C. Phosphorus tribromide (0.70 mL; 7.5 mmol) is added dropwise via a syringe and reaction mixture is stirred at RT for 2 h. NEt3 (1 mL) is added by syringe and the reaction mixture is stirred for 1 h. The mixture is cooled to 0° C. and quenched with the slow addition of 5 mL water, followed by the addition of 2M K2CO3 until mixture is neutral (pH=˜7). The mixture is partitioned between water and EtOAc, the aqueous phase is washed three times with EtOAc and the organic layers are combined, dried over anhydrous sodium sulfate, filtered and deposited on silica. Purification by column chromatography on silica gel (pre-washed with 1% NEt3) using a solvent gradient of hexanes to EtOAc led to the isolation of the desired product as white crystals (1.29 g, 69% yield).

1. customthe flask is flushed with argon
2. customreaction mixture
3. stirringthe reaction mixture is stirred for 1 h
4. temperatureThe mixture is cooled to 0° C.
5. customquenched with the slow addition of 5 mL water
6. additionfollowed by the addition of 2M K2CO3 until mixture
7. customThe mixture is partitioned between water and EtOAc
8. washthe aqueous phase is washed three times with EtOAc
9. dry with materialdried over anhydrous sodium sulfate
10. filtrationfiltered
11. customPurification by column chromatography on silica gel (pre-washed with 1% NEt3)

ORD record

ord-427e957523a444bcba77739337e19954

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08816082B2