Ethyl chloroformate → Ethyl 3,5-dibromoisonicotinate

Temperature

-78 °C

To a solution of 3,5-dibromopyridine (5 g, 21.11 mmol) in THF was added LDA (2 M in THF, 12.66 ml, 25.33 mmol) at −78° C. The mixture was stirred at −78° C. for 45 min. Then ethyl carbonochloridate (2.29 g, 21.11 mmol) was added and the mixture stirred at −78° C. for 1 hours. After reaction completed, the reaction was quenched by addition of 5 mL of saturated NH4Cl and extracted with EtOAc. The extractions were combined, washed with H2O, dried over Na2SO4 and concentrated under vacuum. The residue was purified by flash column (Eluent: PE/EtOAc=10:1), to give ethyl 3,5-dibromoisonicotinate as a yellow solid. (1.9 g, yield 29%) LCMS (M+H+) m/z: calcd 306.8. found 309.7.

1. stirringthe mixture stirred at −78° C. for 1 hours
2. customAfter reaction
3. customthe reaction was quenched by addition of 5 mL of saturated NH4Cl
4. extractionextracted with EtOAc
5. extractionThe extractions
6. washwashed with H2O
7. dry with materialdried over Na2SO4
8. concentrationconcentrated under vacuum
9. customThe residue was purified by flash column (Eluent: PE/EtOAc=10:1)

ORD record

ord-e5995e6bb43b4cb283d58ea989579d1c

Source dataset

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09206128B2