Diethyl Ether → Ethyl 2-diazo-2-formylacetate

Temperatur

40 °C

Oxalyl chloride (4.7 g, 3.1 mL, 37.0 mmol) was added to a cold (0-4° C.) solution of DMF (2.25 g, 2.4 mL, 30.8 mmol) in CHCl3 (20 mL) and stirring was continued for 10 minutes. The reaction mixture was heated at 40° C. for 10 minutes and cooled to −10° C. Diazo-acetic acid ethyl ester (3.5 g, 3.5 mL, 30.6 mmol) was then added and stirred at room temperature for 1 hr. Reaction mixture was concentrated to get the residue. Ether was then added, filtered the solid precipitated and dissolved in 10% aq HAc (10 mL) and stirring was continued for 1 hr. The reaction mixture was extracted with ether, washed with saturated sodium bicarbonate solution and brine. The organic phase was dried over Na2SO4 and concentrated under reduced pressure to afford 590 mg (21% Yield) of 2-diazo-3-oxo-propionic acid ethyl ester. 1H NMR (CDCl3): δ 9.7 (s, 1H), 4.4 (q, 2H), 1.4 (t, 3H).

1. temperaturecooled to −10° C
2. stirringstirred at room temperature for 1 hr
3. customReaction mixture
4. concentrationwas concentrated
5. customto get the residue
6. filtrationfiltered the solid
7. customprecipitated
8. dissolutiondissolved in 10% aq HAc (10 mL)
9. stirringstirring
10. waitwas continued for 1 hr
11. extractionThe reaction mixture was extracted with ether
12. washwashed with saturated sodium bicarbonate solution and brine
13. dry with materialThe organic phase was dried over Na2SO4
14. concentrationconcentrated under reduced pressure

ORD-Eintrag

ord-84170e6c6e6d4048b1d23b11ed2fd193

Quelldatensatz

uspto-grants-2010_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07842696B2