Methyl formate → 2,4-Dichloropyridine-3-carbaldehyde

Temperature

0 °C

A solution of diisopropylamine (2.6 mL, 18.5 mmol) in THF (18.5 mL) was stirred at −78° C. as a 2.5 N solution of n-butyl lithium (7.4 mL, 18.5 mmol) was added. The solution was stirred at 0° C. for 30 minutes, then cooled to −78° C. for 30 minutes before the addition of 2,4-dichloropyridine (2 mL, 18.5 mmol). The solution was stirred at −78° C. for another 30 minutes before the addition of methyl formate (1.14 mL, 18.5 mmol). The solution was stirred for 30 minutes then was partitioned between ethyl acetate and saturated aqueous NaHCO3. The organic layer was dried with MgSO4, filtered and concentrated. The residue was purified by chromatography (silica gel, hexane to 3:7 ethyl acetate:hexanes) to provide 2,4-dichloro-3-pyridinecarbaldehyde (2.18 g, 67%). 1H NMR (400 MHz, DMSO-d6): δ 10.29 (s, 1H), 8.54 (d, J=5 Hz, 1H), 7.75 (d, J=5 Hz, 1H).

1. additionwas added
2. stirringThe solution was stirred for 30 minutes
3. customthen was partitioned between ethyl acetate and saturated aqueous NaHCO3
4. dry with materialThe organic layer was dried with MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by chromatography (silica gel, hexane to 3:7 ethyl acetate:hexanes)

ORD record

ord-05bfdab144ae4435841921bedc8add4d

Source dataset

uspto-grants-2011_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07960552B2