Hydrochloric Acid → HCID 10932262, compound
Reaction equation
[F:1][C:2]1[C:10]([F:11])=[C:9](F)[C:8]([F:13])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[OH-:14].[Na+].[Cl-].[Ca+2].[Cl-].Cl>O>[OH:14][C:9]1[C:8]([F:13])=[CH:7][C:3]([C:4]([OH:6])=[O:5])=[C:2]([F:1])[C:10]=1[F:11]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 100 °C
Procedure
50 g (0.258 mol) of 2,3,4,5-tetrafluorobenzoic acid and 41.4 g (1.04 mol) of sodium hydroxide are introduced first into 687 g of water, the resulting solution is heated to 100° C. and stirred at this temperature for 12 to 14.5 hours. The end point of the reaction is determined by gas chromatography. 57.2 g of calcium chloride are then added, and the pH is brought to 1 with 30% hydrochloric acid. The solutionis continuously extracted with MTBE (methyl tert.-butyl ether) for 16 hours, and the solvent is then distilled off. The dry residue (44.6 g) is recrystallized at 145° C. from 1,2-dichlorobenzene to give 42.1 g (0.219 mol, 85%) of white to slightly beige-colored 4-hydroxy-2,3,5-trifluorobenzoic acid which gives the expected values in all analytical tests. The 3-hydroxy-2,4,5-trifluorobenzoic acid content ofless than 5 mol % of the crude product also formed in the reaction is completely removed by dissolution and reprecipitation (recrystallization).
Workup
- extractionThe solutionis continuously extracted with MTBE (methyl tert.-butyl ether) for 16 hours
- distillationthe solvent is then distilled off
- customThe dry residue (44.6 g) is recrystallized at 145° C. from 1,2-dichlorobenzene
Sources & evidence
- ORD record
- ord-eae8d0b9c57641329ce1590ad8708ed7
- Source dataset
- uspto-grants-1995_08
- Patent number
- US05446198
Reaction notes
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