Reaction #810702

Reaction equation

ethyl glyoxalate

sodium hydride

6-chloro-5-nitro-nicotinic acid methyl ester

→

product

Yield 68.2%

6-Ethoxycarbonylmethoxy-5-nitro-nicotinic acid methyl ester

Yield 68.2%

Solvents

dioxan

dioxan

Conditions

Workup

1. 1
   Temperaturecooled in ice
2. 2
   Otherat room temperature
3. 3
   Otherovernight
4. 4
   OtherThe reaction mixture was evaporated to dryness, sodium bicarbonate solution
5. 5
   workup.ADDITIONwas added to pH 7
6. 6
   Extractionthe mixture extracted with chloroform
7. 7
   Dryingdried (anhydrous sodium sulfate)
8. 8
   Otherevaporated
9. 9
   Otherto afford a semi-solid
10. 10
    Otherthat was chromatographed on silica gel [dichloromethane-hexane (1:1)

Procedure

A solution of ethyl glyoxalate (2.80 g) in dry dioxan (100 mL), cooled in ice, was treated with sodium hydride (60% dispersion in oil; 1.30 g) and the mixture was heated at 50° C. for 30 minutes and cooled in ice. A solution of 6-chloro-5-nitro-nicotinic acid methyl ester (5.25 g) [prepared as described by A. H. Berrie et al. J. Chem. Soc. 2590-2594 (1951)] in dioxan (40 mL) was added and the solution was stirred at 0° C. for 30 minutes and then at room temperature overnight. The reaction mixture was evaporated to dryness, sodium bicarbonate solution was added to pH 7, and the mixture extracted with chloroform, dried (anhydrous sodium sulfate) and evaporated to afford a semi-solid that was chromatographed on silica gel [dichloromethane-hexane (1:1) then dichloromethane] to afford the product (4.70 g).

Source