Sulfuric Acid → 6-Ethoxy-3-(trichloromethyl)phthalide
Reaction equation
[CH2:1]([O:3][C:4]1[CH:5]=[C:6]([CH:10]=[CH:11][CH:12]=1)[C:7]([OH:9])=[O:8])[CH3:2].S(=O)(=O)(O)O.[Cl:18][C:19]([Cl:23])([Cl:22])[CH:20]=O>O>[CH2:1]([O:3][C:4]1[CH:5]=[C:6]2[C:10]([CH:20]([C:19]([Cl:23])([Cl:22])[Cl:18])[O:8][C:7]2=[O:9])=[CH:11][CH:12]=1)[CH3:2]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 25 °C
Procedure
To a stirred solution of 6.6 g (40 mmoles) of 3-ethoxybenzoic acid in 50 ml. of concentrated sulfuric acid were added dropwise over fifteen minutes 8.0 g (55 mmoles) of trichloroacetaldehyde (chloral). The reaction mixture was stirred for twelve hours at 25° C., and then an additional 8.0 g of chloral were added in one portion and the mixture was stirred for an additional three hours. The reaction mixture was next added to 50 g of ice and 50 ml of water, and the aqueous mixture was extracted several times with diethyl ether. The ethereal extracts were combined, washed with aqueous sodium bicarbonate and then with fresh water, and dried. The solvent was removed by evaporation under reduced pressure to provide an oil. The oil solidified and then was crystallized from ethanol to afford 1.1 g of 6-ethoxy-3-(trichloromethyl)phthalide. m.p. 112°-114° C.
Workup
- stirringthe mixture was stirred for an additional three hours
- extractionthe aqueous mixture was extracted several times with diethyl ether
- washwashed with aqueous sodium bicarbonate
- dry with materialwith fresh water, and dried
- customThe solvent was removed by evaporation under reduced pressure
- customto provide an oil
- customwas crystallized from ethanol
Sources & evidence
- ORD record
- ord-954fe4421a184edcb4937c9815bb2e12
- Source dataset
- uspto-grants-1982_06
- Patent number
- US04333923
Reaction notes
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