Phenol → 2,5-Bis(4-hydroxyphenyl)-1,3,4-oxadiazole

HRID 892498Notes

Reaction equation

HRID 892498 reaction equation
[OH:1][C:2]1[CH:11]=[CH:10][C:5]([C:6]([NH:8][NH2:9])=[O:7])=[CH:4][CH:3]=1.C1(O[C:19](=O)[C:20]2[CH:25]=[CH:24][C:23]([OH:26])=[CH:22][CH:21]=2)C=CC=CC=1.C1(O)C=CC=CC=1>>[OH:26][C:23]1[CH:24]=[CH:25][C:20]([C:19]2[O:7][C:6]([C:5]3[CH:10]=[CH:11][C:2]([OH:1])=[CH:3][CH:4]=3)=[N:8][N:9]=2)=[CH:21][CH:22]=1

Participants

4

Reactant 3

HCID 996PhenolHCID 17424-Hydroxybenzoic acid hydrazideHCID 87250Phenylparaben

Product 1

HCID 5787062,5-Bis(4-hydroxyphenyl)-1,3,4-oxadiazoleYield 45%

Conditions

Temperature
210 °C

Procedure

Into a 250 ml three neck round bottem flask equipped with a magnetic stirbar, nitrogen inlet, glass stopper and distillation head is placed 4-hydroxybenzoic hydrazide (60.9 g, 0.4 mol) and phenyl-4-hydroxybenzoate (85.7 g, 0.4 mol). The mixture is heated to approximately 210° C. by use of a Wood's metal bath. The solids melt and phenol begins to evolve and is removed via the distillation head. The melt begins to solidify after about 15-20 minutes. The temperature is then increased to 300° C. and held for approximately one hour while under nitrogen. After cooling, the tan solid is pulverized and stirred with methanol (150-200 ml). The undissolved solid is collected and dried at 150° C. in a forced air oven. The white solid (approximately 56 g) is recrystallized from N,N-dimethylacetamide (DMAc, 225 ml) and water (105 ml) and after drying at 200° C. under vacuum (45.7 g, 45% yield), it exhibited a melting point of 347° C. by differential thermal analysis (DTA). [Y. Iwakura, U. Keikichi, Y. Imai, and Y. Takase, Die Makromoleculare Chemie, 95, 261 (1966) melting point 338° C⟧ Elemental analysis for C14H10O3N2. Calculated: C, 66.13%; H, 3.96%; O, 18.88%; N, 11.02%. Found C, 66.17%; H, 4.05%; N, 11.12%.

Workup

  1. customis removed via the distillation head
  2. temperatureThe temperature is then increased to 300° C.
  3. waitheld for approximately one hour while under nitrogen
  4. temperatureAfter cooling
  5. customThe undissolved solid is collected
  6. customdried at 150° C. in a forced air oven
  7. customThe white solid (approximately 56 g) is recrystallized from N,N-dimethylacetamide (DMAc, 225 ml) and water (105 ml)
  8. customafter drying at 200° C. under vacuum (45.7 g, 45% yield), it

Sources & evidence

ORD record
ord-a47434401578420fb053755fe6dd0c3e
Source dataset
uspto-grants-1992_06
Patent number
US05118781

Reaction notes

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