Acetic Anhydride → Dimethyl 1,2,3,6-tetrahydro-4-acetyl-phthalate

HRID 2248078Notes

Reaction equation

HRID 2248078 reaction equation
[C:1]([O:13][CH3:14])(=[O:12])[CH:2]1[CH2:11][CH:10]=[CH:9][CH2:8][CH:3]1[C:4]([O:6][CH3:7])=[O:5].[C:15](OC(=O)C)(=[O:17])[CH3:16].[Sn](Cl)(Cl)(Cl)Cl>O>[C:15]([C:9]1[CH2:8][CH:3]([C:4]([O:6][CH3:7])=[O:5])[CH:2]([CH2:11][CH:10]=1)[C:1]([O:13][CH3:14])=[O:12])(=[O:17])[CH3:16]

Participants

5

Procedure

10 g dimethyl 1,2,3,6-tetrahydro-phthalate (II) was treated at -5° C. with 25 ml of acetic anhydride in the presence of 9 ml of tin tetrachloride. The reaction mixture was poured into iced water and extracted with diethyl ether. The organic phase was washed with a saturated aqueous solution of sodium bicarbonate and then with water, and was then evaporated to dryness under vacuum. The obtained oil was dissolved in benzene, treated with a methanolic solution of hydrogen chloride. The solution was evaporated to dryness and the residue was purified by chromatography on column of silica gel to give 9 g of the title compound in 75% overall yield. mass spectrum: m/z 240 (M+.)

Workup

  1. extractionextracted with diethyl ether
  2. washThe organic phase was washed with a saturated aqueous solution of sodium bicarbonate
  3. customwith water, and was then evaporated to dryness under vacuum
  4. dissolutionThe obtained oil was dissolved in benzene
  5. additiontreated with a methanolic solution of hydrogen chloride
  6. customThe solution was evaporated to dryness
  7. customthe residue was purified by chromatography on column of silica gel

Sources & evidence

ORD record
ord-46171b18fad24be5b68080e2eb898e0d
Source dataset
uspto-grants-1991_08
Patent number
US05037970

Reaction notes

Loading…