Acetic Anhydride → 4,7-Epoxyisobenzofuran-1,3-dione, hexahydro-

HRID 68482Notes

Reaction equation

HRID 68482 reaction equation
C(OC(=O)C)(=O)C.[CH2:8]1[C@H:13]2[O:14][C@H:10]([C@H:11]([C:18]([OH:20])=[O:19])[C@@H:12]2[C:15]([OH:17])=O)[CH2:9]1>C1C=CC=CC=1>[CH2:9]1[CH:10]2[O:14][CH:13]([CH:12]3[C:15](=[O:17])[O:20][C:18](=[O:19])[CH:11]32)[CH2:8]1

Participants

4

Reactant 2

HCID 7918Acetic AnhydrideHCID 168842rel-(1R,2S,3R,4S)-7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic acid

Product 1

HCID 930044,7-Epoxyisobenzofuran-1,3-dione, hexahydro-Yield 50.6%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Conditions

Temperature
80 °C

Procedure

As shown in scheme 1, we prepared endothal anhydride by adding acetic anhydride (0.5 mL) (4) to a suspension of Endothall (186 mg) (3) in benzene (3 mL) and the mixture was then stirred until the solid had gone into solution (2 hours). The solution was heated under vacuum to remove the benzene and the residue was then heated at 80° C. for 30 min. Petroleum ether (5 mL) was then added and the desired anhydride spontaneously crystallized. The product was removed by filtration washed with a little petroleum ether to give the pure product (85 mg) which was used immediately in the following two preparations.

Workup

  1. customhad gone into solution (2 hours)
  2. temperatureThe solution was heated under vacuum
  3. customto remove the benzene
  4. additionPetroleum ether (5 mL) was then added
  5. customthe desired anhydride spontaneously crystallized
  6. customThe product was removed by filtration
  7. washwashed with a little petroleum ether

Sources & evidence

ORD record
ord-4683cf18ad7e4cdbb68988e42da94880
Source dataset
uspto-grants-2014_09
Patent number
US08822461B2

Reaction notes

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