Hydrochloric Acid → HCID 19780703, compound
Reaction equation
[CH3:1][C:2]1[O:3][C:4]2[C:9]([C:10](=[O:13])[C:11]=1[CH3:12])=[CH:8][C:7]([S:14](Cl)(=[O:16])=[O:15])=[CH:6][CH:5]=2.C(=O)([O-])O.[Na+].S([O-])([O-])=O.[Na+].[Na+].Cl>O>[CH3:1][C:2]1[O:3][C:4]2[C:9]([C:10](=[O:13])[C:11]=1[CH3:12])=[CH:8][C:7]([S:14]([OH:16])=[O:15])=[CH:6][CH:5]=2Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 75 °C
Procedure
2,3-Dimethyl-4-oxo-4H-chromene-6-sulphonyl chloride (obtained as described in J. Org. Chem., 1956, page 1104) (3.05 g, 11.2 mM) was added in small portions to a vigorously stirred solution of sodium hydrogen carbonate (1.88 g, 22.4 mM) and anhydrous sodium sulphite (2.54 g, 20.2 mM) in water (14 ml) at 75° C. When the addition was complete, the mixture was vigorously stirred at 75° C. for 45 minutes. The clear solution was allowed to cool to ambient temperature, diluted to 20 ml with water, and acidified with 2M hydrochloric acid at 0° C. The precipitated solid was collected by filtration, washed with a minimum of cold water, and air dried to give 2,3-dimethyl-4-oxo-4H-chromene-6-sulphinic acid as a white solid (2.16 g). This acid was converted to its sodium salt by addition of a methanolic solution of sodium methoxide [prepared from sodium (0.12 g) and methanol (100 ml)], and evaporation of the solution. The resultant sodium salt, obtained as a cream solid, was used immediately without further purification.
Workup
- additionWhen the addition
- temperatureto cool to ambient temperature
- filtrationThe precipitated solid was collected by filtration
- washwashed with a minimum of cold water, and air
- customdried
Sources & evidence
- ORD record
- ord-1243023b17c54a0a8a006e75256f1d86
- Source dataset
- uspto-grants-1993_02
- Patent number
- US05185452
Reaction notes
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