Potassium Hydroxide → (1,3-Dithiol-2-ylidene)malonic acid monomethyl ester

HRID 1737937Notes

Reaction equation

HRID 1737937 reaction equation
[S:1]1[CH:5]=[CH:4][S:3][C:2]1=[C:6]([C:11]([O:13]C)=[O:12])[C:7]([O:9][CH3:10])=[O:8].[OH-].[K+]>CO.O>[S:1]1[CH:5]=[CH:4][S:3][C:2]1=[C:6]([C:7]([O:9][CH3:10])=[O:8])[C:11]([OH:13])=[O:12]

Participants

5

Reactant 2

HCID 14797Potassium HydroxideHCID 9834557Propanedioic acid, 1,3-dithiol-2-ylidene-, dimethyl ester

Product 1

HCID 15432125(1,3-Dithiol-2-ylidene)malonic acid monomethyl esterYield 84.4%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Conditions

Temperature
50 °C

Procedure

Dimethyl 2-(1,3-dithiol-2-ylidene)malonate (2) (116 g) was suspended in methanol (2 l), to which a solution of 33.5 g of 85% potassium hydroxide in water (250 ml) was added. The resulting mixture was heated under reflux for 8 hours. After the solvent was removed, water (2.5 l) was added and the resulting mixture was heated to 50° C. Insoluble matter was filtered off. Concentrated hydrochloric acid (50 ml) was added to the filtrate to acidify the same. The resultant precipitate was collected by filtration and after washing, was dried at 40° C. in air, whereby 2-(1,3-dithiol-2-ylidene)-3-methoxy-3-oxopropionic acid (3) (92 g, yield: 84%) was obtained.

Workup

  1. additionwas added
  2. temperatureThe resulting mixture was heated
  3. temperatureunder reflux for 8 hours
  4. customAfter the solvent was removed
  5. additionwater (2.5 l) was added
  6. filtrationInsoluble matter was filtered off
  7. additionConcentrated hydrochloric acid (50 ml) was added to the filtrate
  8. filtrationThe resultant precipitate was collected by filtration
  9. washafter washing
  10. customwas dried at 40° C. in air

Sources & evidence

ORD record
ord-2bfd525b29954f70b53fa5631009bad7
Source dataset
uspto-grants-1999_10
Patent number
US05962509

Reaction notes

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