Dimethylformamide → Methyl 2,5-Dichloronicotinate

A solution of 2,5-dichloronicotinic acid (25.0 g, 130 mmol) in methylene chloride (650 mL) was treated with oxalyl chloride (22 mL, 260 mmol) followed by N,N-dimethylformamide (1.0 mL) and stirred at room temperature for 18 hours. The gas evolution ceased and the reaction mixture was concentrated. The acid chloride intermediate was taken up in methylene chloride (300 mL), cooled to 0° C. and treated with methanol (26 mL). The reaction was stirred at 0° C. for 30 minutes, allowed to warm to room temperature and was concentrated in vacuo to give an oil. This oil was taken up in ethyl acetate, washed with water saturated potassium carbonate, brine, dried over magnesium sulfate and concentrated to give methyl 2,5-dichloronicotinate (24.5 g, 92%) as an oil. LCMS calculated for C7H6Cl2NO2(M+H)+: m/z=205.9, 207.9. found: 205.9, 207.9.

1. concentrationthe reaction mixture was concentrated
2. temperaturecooled to 0° C.
3. additiontreated with methanol (26 mL)
4. stirringThe reaction was stirred at 0° C. for 30 minutes
5. temperatureto warm to room temperature
6. concentrationwas concentrated in vacuo
7. customto give an oil
8. washwashed with water saturated potassium carbonate, brine
9. dry with materialdried over magnesium sulfate
10. concentrationconcentrated

ORD record

ord-c1d59aab1f7f4d6d96ac3dff58d6a110

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09193721B2