Acetic Anhydride → Dimethyl 1,2,3,6-tetrahydro-4-acetyl-phthalate
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
Reactant 3
Product 1
Reagents, catalysts & solvents 1
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
- extractionextracted with diethyl ether
- washThe organic phase was washed with a saturated aqueous solution of sodium bicarbonate
- customwith water, and was then evaporated to dryness under vacuum
- dissolutionThe obtained oil was dissolved in benzene
- additiontreated with a methanolic solution of hydrogen chloride
- customThe solution was evaporated to dryness
- 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
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