Carbon Dioxide → 4-Chloro-2-fluoro-3-(methylthio)benzoic acid
Reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([F:8])[C:3]=1[S:9][CH3:10].[C:11](=[O:13])=[O:12]>CCCCCC.O1CCCC1>[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:11]([OH:13])=[O:12])=[C:4]([F:8])[C:3]=1[S:9][CH3:10]Participants
5
Reactant 2
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- -78 °C
Procedure
n-Butylithium (2.5M in hexane, 140 ml) was added to a stirred, cooled solution of crude 2-chloro-6-fluorothioanisole (60.0 g) in dry tetrahydrofuran while maintaining the temperature below -70° C. The mixture was stirred at -78° C. for 3.5 hours then poured onto solid carbon dioxide pellets. It was stirred and allowed to warm to room temperature. It was evaporated to dryness and the residue was dissolved in water and washed with ether. The aqueous layer was acidified to pH1 and extracted with ether, washed with water, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was triturated with hexane and filtered to give 4-chloro-2-fluoro-3-(methylsulphenyl)benzoic acid as a white solid, m.p. 183°-185° C.
Workup
- temperaturewhile maintaining the temperature below -70° C
- stirringIt was stirred
- temperatureto warm to room temperature
- customIt was evaporated to dryness
- dissolutionthe residue was dissolved in water
- washwashed with ether
- extractionextracted with ether
- washwashed with water
- dry with materialdried (MgSO4)
- filtrationfiltered
- customThe filtrate was evaporated to dryness
- customthe residue was triturated with hexane
- filtrationfiltered
Sources & evidence
- ORD record
- ord-34596e180732413fa4e5a6f09c5b0398
- Source dataset
- uspto-grants-1999_01
- Patent number
- US05856274
Reaction notes
Loading…