Methyl cyanoacetate → HCID 86612866, Verbindung

Into a dried 3L three neck-round bottom flask with a stirrer bar, nitrogen-inlet, thermocouple and a addition funnel were charged 150 g (851.26 mmol) 3-(dimethoxymethyl)-2-methoxyoxolane, 355.27 g (3.48 mol) Ac2O and 2.12 g (15.55 mmol) ZnCl2 and the mixture was heated for 1.25-1.5 h at 100-120° C. to reflux. The solution started to become brown and a small portion of solvent was distilled off at atmospheric pressure. To the reaction mixture 76.7 g (774 mmol) methylcyanacetate was slowly added over 1 h while continuing to distill off solvent. After the addition was completed, the reaction mixture was evacuated and the residual solvent was distilled off. The residue was treated with 224 g MeOH and again evacuated and the solvent was distilled off. The residual black oil was charged with 500 ml CH2Cl2 and washed twice with 500 ml water. The solvent was distilled off under reduced pressure and the residue was treated with a mixture of 350 ml MTBE and 285 ml heptane. The reaction mixture was heated to reflux at 55-60° C. for 1½ h, then cooled down to 0° C. and kept at 0° C. for 16 h. The crystals were filtered off and three times washed with cold 250 ml MTBE.

1. dry with materialInto a dried 3L three neck-round bottom flask with a stirrer bar, nitrogen-inlet
2. temperatureto reflux
3. distillationa small portion of solvent was distilled off at atmospheric pressure
4. distillationto distill off solvent
5. additionAfter the addition
6. customthe reaction mixture was evacuated
7. distillationthe residual solvent was distilled off
8. additionThe residue was treated with 224 g MeOH
9. customagain evacuated
10. distillationthe solvent was distilled off
11. additionThe residual black oil was charged with 500 ml CH2Cl2
12. washwashed twice with 500 ml water
13. distillationThe solvent was distilled off under reduced pressure
14. additionthe residue was treated with a mixture of 350 ml MTBE and 285 ml heptane
15. temperatureThe reaction mixture was heated
16. temperatureto reflux at 55-60° C. for 1½ h
17. temperaturecooled down to 0° C.
18. filtrationThe crystals were filtered off
19. washthree times washed with cold 250 ml MTBE

ORD-Eintrag

ord-4921d760e87b42aba5b78d9ffa1e601b

Quelldatensatz

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07282583B2