Sulfuric Acid → 4-Methoxybenzenesulfonic acid
Reaction equation
[S:1](=[O:5])(=O)([OH:3])[OH:2].[CH3:6][O:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1>O>[CH3:6][O:7][C:8]1[CH:13]=[CH:12][C:11]([S:1]([OH:3])(=[O:5])=[O:2])=[CH:10][CH:9]=1Participants
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 82.5 °C
Procedure
560 g of 98% sulfuric acid was dropped into 600 g of methoxybenzene. Then, while the stirring was continued, the temperature was raised into 80 to 85° C., reacting for 3 hours. After the reaction, distillation water was added, adjusting the concentration into 55%. Then, the temperature at about 40° C. was gradually cooled. Upon the temperature reached at 20° C., a small amount of a crystalline of p-methoxybenzenesulfonic acid (4-methoxybenzenesulfonic acid), which was provided in advance, was added, generating crystalline deposition of p-methoxybenzenesulfonic acid in the system. The crystalline as obtained was collected by filtering, into which water was added and the liquid temperature was again raised at 40° C. to dissolve. The concentration was adjusted to have 55%. Then, the temperature at about 40° C. was gradually cooled. Upon the temperature reached at 20° C., a small amount of a crystalline of p-methoxybenzenesulfonic acid, which was provided in advance, was added again, generating crystalline deposition of p-methoxybenzenesulfonic acid. The crystalline was collected by filtration so as to obtain methoxybenzenesulfonic acid in which the para compound was included at 98 mole % in the whole of methoxybenzenesulfonic acid.
Workup
- additionwas added
- concentrationthe concentration into 55%
- temperatureThen, the temperature at about 40° C. was gradually cooled
- customreached at 20° C.
Sources & evidence
- ORD record
- ord-2777e50cb36d42f8bc4203acadae30b5
- Source dataset
- uspto-grants-2012_12
- Patent number
- US08324341B2
Reaction notes
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