Hydrochloric Acid → 3-Chloro-4-methylpyridin-2-ol

HRID 1679398Notes

Reaction equation

HRID 1679398 reaction equation
N([O-])=O.[Na+].N[C:6]1[C:7]([OH:13])=[N:8][CH:9]=[CH:10][C:11]=1[CH3:12].[ClH:14]>O.S>[Cl:14][C:6]1[C:7]([OH:13])=[N:8][CH:9]=[CH:10][C:11]=1[CH3:12]

Participants

6

Reactant 3

HCID 313Hydrochloric Acid2×HCID 23668193Sodium NitriteHCID 178428605HCID 178428605, compound

Product 1

HCID 1784286033-Chloro-4-methylpyridin-2-ol

Reagents, catalysts & solvents 2

HCID 402Hydrogen SulfideSolventHCID 962WaterSolvent3×

Procedure

A solution sodium nitrite (2.38 g) in water (10 ml) was added dropwise to a stirred mixture of 3-amino-2-hydroxy-methylpyridine (4.8 g) in aqueous hydrochloric acid (48% 10 ml) and water (5 ml) at 0°-5° C. This solution of the diazonium salt was added to a hot solution of cuprous chloride (2.5 g) in conc. hydrochloric acid and following cessation of nitrogen evolution the mixture was heated on the steam bath for 0.5 hours, diluted with water and saturated with hydrogen sulphide. Filtration, concentration to low bulk and extraction with chloroform yielded 3-chloro-2-hydroxy-methyl-pyridine (3.7 g), m.p. 42°-44° (from n-pentane). This was dissolved in aqueous hydrobromic acid (48%, 50 ml), cysteamine hydrochloride (3.22 g) added and the solution obtained was heated under reflux for 6 hours. Concentration, followed by recrystallisation from aqueous ethanol afforded 2-[(2-aminoethyl)thiomethyl]-3-chloropyridine dihydrobromide (6.0 g), m.p. 250°.

Workup

  1. temperaturewas heated on the steam bath for 0.5 hours
  2. filtrationFiltration, concentration
  3. extractionto low bulk and extraction with chloroform

Sources & evidence

ORD record
ord-f40b992fd9ad4f9dbe62f73d96a0af2e
Source dataset
uspto-grants-1978_03
Patent number
US04080459

Reaction notes

Loading…