Phosphorus oxychloride → 4-Chloro-3-methyl-6-phenyl[1,2]oxazolo[5,4-b]pyridine

HRID 1287647Notes

Reaction equation

HRID 1287647 reaction equation
[CH3:1][C:2]1[C:10]2[C:9](O)=[CH:8][C:7]([C:12]3[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=3)=[N:6][C:5]=2[O:4][N:3]=1.P(Cl)(Cl)([Cl:20])=O>>[Cl:20][C:9]1[CH:8]=[C:7]([C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[N:6]=[C:5]2[O:4][N:3]=[C:2]([CH3:1])[C:10]=12

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178434713HCID 178434713, compound

Product 1

HCID 215056964-Chloro-3-methyl-6-phenyl[1,2]oxazolo[5,4-b]pyridine

Procedure

6.8 g. of 3-methyl-6-phenylisoxazolo[5,4-b]pyridin-4-ol (0.03 mol.) are refluxed in 60 ml. of phosphorous oxychloride for 3 hours. the excess phosphorous oxychloride is removed in vacuo and the oily residue is treated with ice water. The compound becomes solid. The compound is extracted with chloroform, washed with an aqueous sodium carbonate solution (10%) and again with water. Evaporation of the dried (Na2SO4) and charcoal treated chloroform extract provides 6.3 g. (86%) of 4-chloro-3-methyl-6-phenylisoxazolo[5,4-b]-pyridine which is recrystallized from ligroin and melts at 130°-131°.

Workup

  1. customthe excess phosphorous oxychloride is removed in vacuo
  2. additionthe oily residue is treated with ice water
  3. extractionThe compound is extracted with chloroform
  4. washwashed with an aqueous sodium carbonate solution (10%) and again with water
  5. customEvaporation of the
  6. dry with materialdried (Na2SO4) and charcoal
  7. additiontreated chloroform
  8. extractionextract
  9. customprovides 6.3 g
  10. custom(86%) of 4-chloro-3-methyl-6-phenylisoxazolo[5,4-b]-pyridine which is recrystallized from ligroin and melts at 130°-131°

Sources & evidence

ORD record
ord-e8a83c9a69e34ce8a792aa72bf210d39
Source dataset
uspto-grants-1976_10
Patent number
US03985760

Reaction notes

Loading…