Hydrochloric Acid → 2-Vinylcyclopropane-1,1-dicarboxylic acid monomethyl ester

HRID 1419598Notes

Reaction equation

HRID 1419598 reaction equation
[CH3:1][O:2][C:3]([C:5]1([C:10]([O:12]C)=[O:11])[CH2:7][CH:6]1[CH:8]=[CH2:9])=[O:4].COC(=O)CC(OC)=O.BrC/C=C/CBr.[OH-].[K+].Cl>CO.[Cl-].[Cl-].[Ca+2].O.C(OCC)C>[CH3:1][O:2][C:3]([C:5]1([C:10]([OH:12])=[O:11])[CH2:7][CH:6]1[CH:8]=[CH2:9])=[O:4]

Participants

10

Reactant 5

HCID 313Hydrochloric AcidHCID 7943Dimethyl malonateHCID 14797Potassium HydroxideHCID 641245trans-1,4-Dibromo-2-buteneHCID 104649921,1-Dimethyl 2-ethenylcyclopropane-1,1-dicarboxylate

Product 1

HCID 108559152-Vinylcyclopropane-1,1-dicarboxylic acid monomethyl esterYield 83%

Reagents, catalysts & solvents 4

HCID 887MethanolSolventHCID 962WaterSolvent2×HCID 3283Diethyl EtherSolventHCID 5284359Calcium ChlorideSolvent

Procedure

36.8 g (0.2 mol) of 2-vinyl cyclopropane-1,1-dicarboxylic acid dimethyl ester, obtainable from malonic acid dimethyl ester and trans-1,4-dibromobut-2-ene (cf U.S. Pat. No. 4,713,478 and U.S. Pat. No. 4,713,479), are dissolved in 65 ml of methanol in a 100 ml two-necked flask with a thermometer, magnetic stirrer and CaCl2 tube, and the solution is cooled to ca 50° C. with iced water. Then 13.3 g (0.2 mol) of KOH are added in portions in such a way that the temperature does not rise above 15° C. In order to complete the reaction, stirring is continued for 12 hours, and then volatile components are removed in a rotary evaporator in vacuo (50 mbar) at 50° C. The oil obtained (ca 43 g) is dissolved in 50 ml of water and is adjusted to a pH of ca 2-3 with concentrated hydrochloric acid accompanied by cooling. The organic phase is taken up in 100 ml of diethyl ether, extracted twice more with in each case 100 ml of diethyl ether, and the combined ether phases are dried over anhydrous Na2SO4. The solution is stabilized with 0.01 g of hydroquinone monomethyl ether, concentrated in vacuo and dried under a medium high vacuum. The result is 28.2 g (83% yield) of a colourless liquid.

Workup

  1. customdoes not rise above 15° C
  2. customthe reaction
  3. customvolatile components are removed in a rotary evaporator in vacuo (50 mbar) at 50° C
  4. customThe oil obtained (ca 43 g)
  5. temperatureby cooling
  6. extractionextracted twice more with in each case 100 ml of diethyl ether
  7. dry with materialthe combined ether phases are dried over anhydrous Na2SO4
  8. concentrationconcentrated in vacuo
  9. customdried under a medium high vacuum

Sources & evidence

ORD record
ord-20434bacbcf148ae8eb1f79db88110b6
Source dataset
uspto-grants-1999_03
Patent number
US05886212

Reaction notes

Loading…