Hydrochloric Acid → 2-(3-Methylthiophen-2-YL)acetic acid
Reaction equation
O.NN.[CH3:4][C:5]1[CH:9]=[CH:8][S:7][C:6]=1[C:10](=O)[C:11]([O:13]C)=[O:12].[OH-].[K+].Cl>C(O)COCCO.O>[CH3:4][C:5]1[CH:9]=[CH:8][S:7][C:6]=1[CH2:10][C:11]([OH:13])=[O:12]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- 35 °C
Procedure
112.5 ml (116 g, 2.312 mol) of hydrazine hydrate were added slowly to a solution of 90 g (0.489 mol) of methyl (3-methylthiophen-2-yl)oxoacetate in 260 ml of diethylene glycol, and the mixture was heated at reflux for 30 min. After cooling to 30-40° C., 82 g (1.246 mol) of potassium hydroxide were added a little at a time, which was associated with a temperature increase to 70-80° C. with simultaneous evolution of nitrogen. The mixture was then slowly heated to reflux and stirred at this temperature for a total of 5 h. After cooling to room temperature, the mixture was poured into 2 l of water, adjusted to pH=1 using 250 ml of semiconcentrated hydrochloric acid and extracted with ethyl acetate. Drying of the organic phase over magnesium sulphate, filtration and removal of the solvent gave 50 g of (3-methylthiophen-2-yl)acetic acid. Yield: 66%. 1H-NMR (DMSO): δ=7.25 (d, 1H), 6.84 (d, 2H), 3.67 (s, 2H), 2.11 (s, 3H).
Workup
- temperaturethe mixture was heated
- temperatureat reflux for 30 min
- temperatureincrease to 70-80° C. with simultaneous evolution of nitrogen
- temperatureThe mixture was then slowly heated
- temperatureto reflux
- temperatureAfter cooling to room temperature
- extractionextracted with ethyl acetate
- dry with materialDrying of the organic phase over magnesium sulphate, filtration and removal of the solvent
Sources & evidence
- ORD record
- ord-1857c23c946840838cb71308141c55fc
- Source dataset
- uspto-grants-2010_08
- Patent number
- US07781439B2
Reaction notes
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