Nicotinic Acid → 2-(3-Pyridyl)benzothiazole

HRID 1287829Notes

Reaction equation

HRID 1287829 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[SH:8].[C:9](O)(=O)[C:10]1[CH:15]=[CH:14][CH:13]=[N:12][CH:11]=1>C(Cl)(Cl)Cl>[N:12]1[CH:13]=[CH:14][CH:15]=[C:10]([C:9]2[S:8][C:3]3[CH:4]=[CH:5][CH:6]=[CH:7][C:2]=3[N:1]=2)[CH:11]=1

Participants

4

Reactant 2

HCID 938Nicotinic AcidHCID 87132-Aminothiophenol

Product 1

HCID 2359222-(3-Pyridyl)benzothiazole

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

o-Aminothiophenol 36.9 g (0.30 mole) and nicotinic acid 55.5 g (0.45 mole) are dissolved in 600 cc of chloroform and 360 g of polyphosphoric acid ethyl ester (PPE). The resulting solution is heated at reflux for 1 hour. It is then concentrated to dryness. The residue is poured onto 1500 cc of ice-water, and the resulting mixture is brought to pH 10 with 50% NaOH solution. The aqueous mixture is extracted with CHCl3, and the extracts dried (MgSO4), filtered, and concentrated in vacuo. The residue is recrystallized from acetonitrile to yield the title A compound (42.8 g, 68%, of theory).

Workup

  1. temperatureThe resulting solution is heated
  2. temperatureat reflux for 1 hour
  3. concentrationIt is then concentrated to dryness
  4. additionThe residue is poured onto 1500 cc of ice-water
  5. extractionThe aqueous mixture is extracted with CHCl3
  6. dry with materialthe extracts dried (MgSO4)
  7. filtrationfiltered
  8. concentrationconcentrated in vacuo
  9. customThe residue is recrystallized from acetonitrile
  10. customto yield the title A compound (42.8 g, 68%, of theory)

Sources & evidence

ORD record
ord-aaa49fdb4a1947e99981509e25dbf2e4
Source dataset
uspto-grants-1976_10
Patent number
US03985885

Reaction notes

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