Propionic Acid → Ethyl 3-(2-chloroethyl)-3-methylpent-4-enoate

HRID 1731025Notes

Reaction equation

HRID 1731025 reaction equation
[Cl:1][CH2:2][CH2:3][C:4]([CH3:8])=[CH:5][CH2:6]O.[C:9]([O:17]CC)([O:14][CH2:15][CH3:16])(OCC)[CH3:10].C(O)(=O)CC>C(O)C>[Cl:1][CH2:2][CH2:3][C:4]([CH3:8])([CH:5]=[CH2:6])[CH2:10][C:9]([O:14][CH2:15][CH3:16])=[O:17]

Participants

5

Reactant 3

HCID 1032Propionic AcidHCID 66221Triethyl orthoacetateHCID 53755914HCID 53755914, compound

Product 1

HCID 21494877Ethyl 3-(2-chloroethyl)-3-methylpent-4-enoateYield 76%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of 1.97 parts of a 2:1 mixture of E/Z stereoisomers of 5-chloro-3-methyl-2-penten-1-ol in 20 parts by volume of triethyl orthoacetate is added 0.14 part of propionic acid. This solution is heated for 40 hours in an oil bath (~150°) in such a manner that the ethanol that forms during the reaction is slowly distilled through a Vigreaux column. After cooling the solution, 20 parts by volume of pentane and 20 parts by volume of 1 M sulfuric acid are added, and this mixture is stirred vigorously for 5 minutes to hydrolyze the excess triethyl orthoacetate. The mixture is then diluted with 150 parts by volume of water and the product is isolated by pentane extraction. The pentane extracts are washed with saturated sodium bicarbonate, 10% sodium chloride solution, dried over anhydrous magnesium sulfate, and filtered. Removal of the pentane, followed by fractional distillation, yields 2.27 parts (76%) of ethyl 3-[2-chloroethyl]-3-methyl- 4-pentenoate. The formula is: ##STR2##

Workup

  1. distillationis slowly distilled through a Vigreaux column
  2. temperatureAfter cooling the solution, 20 parts by volume of pentane and 20 parts by volume of 1 M sulfuric acid
  3. additionare added
  4. additionThe mixture is then diluted with 150 parts by volume of water
  5. customthe product is isolated by pentane extraction
  6. washThe pentane extracts are washed with saturated sodium bicarbonate, 10% sodium chloride solution
  7. dry with materialdried over anhydrous magnesium sulfate
  8. filtrationfiltered
  9. customRemoval of the pentane
  10. distillationfollowed by fractional distillation

Sources & evidence

ORD record
ord-ea2813443ae34c07987367cc2ab36d4a
Source dataset
uspto-grants-1976_11
Patent number
US03994953

Reaction notes

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