Sodium Hydroxide → 3-Pyridinesulfonic acid
Reaction equation
[S:1](=[O:4])([OH:3])[O-:2].[Na+].[OH-].[Na+].Cl[C:9]1[CH:10]=[N+:11]([O-])[CH:12]=[CH:13][CH:14]=1.[H][H]>O.[Ni]>[N:11]1[CH:12]=[CH:13][CH:14]=[C:9]([S:1]([OH:3])(=[O:2])=[O:4])[CH:10]=1Participants
Conditions
- Temperature
- 145 °C
Procedure
18.7 kg of sodium bisulfite were dissolved in 55.8 liters of water and the pH was adjusted to a pH of 9 to 9.5 with 14.4 kg of sodium hydroxide. To the solution were added 11.7 kg of raw 3-chloro-pyridine-N-oxide and the mixture was heated in an autoclave to 145° C. The reaction mixture was stirred at 145° C. for 17 hours (during the reaction, a pressure of 4 to 5 bars resulted). After completion of the reaction, cooling to 90° C. took place. 1 kg of sodium hydroxide (50 weight %) was added to adjust to alkaline and in a nitrogen atmosphere, 0.5 kg of Raney nickel were added. The suspension was heated to 100° to 110° C. and at this temperature, hydrogen was pressed on with 7 bars. Hydrogenation was carried out for 16 hours and then the mixture was cooled to 70° C. and the catalyst was separated with a pressure filter. The pyridine-3-sulfonic acid was isolated as in Example 4 and purified.
Workup
- customduring the reaction
- customa pressure of 4 to 5 bars resulted)
- customAfter completion of the reaction
- temperaturecooling to 90° C.
- additionwere added
- waitHydrogenation was carried out for 16 hours
- temperaturethe mixture was cooled to 70° C.
- customthe catalyst was separated with a pressure
- filtrationfilter
Sources & evidence
- ORD record
- ord-fa047ae746ea4e12baa717915bb676c3
- Source dataset
- uspto-grants-1992_01
- Patent number
- US05082944
Reaction notes
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