Hydrazine → 3,4-Diphenylpyrazole

HRID 1460714Notes

Reaction equation

HRID 1460714 reaction equation
[C:1]1([C:7]([CH2:9][C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)=O)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.COC(OC)[N:19]([CH3:21])C.[NH2:24]N>>[C:1]1([C:7]2[C:9]([C:10]3[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=3)=[CH:21][NH:19][N:24]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1

Participants

4

Reactant 3

HCID 9321HydrazineHCID 99482-PhenylacetophenoneHCID 78373Dimethylformamide dimethyl acetal

Product 1

HCID 3017433,4-DiphenylpyrazoleYield 92.9%

Conditions

Temperature
120 °C

Procedure

A mixture of deoxybenzoin (50 g, 0.255 mole) and N,N-dimethylformamide dimethyl acetal (37.9 g, 42.5 ml, 0.32 mole) was stirred at 120° C. under an atmosphere of nitrogen. After 30 minutes the heating source was removed and hydrazine (24 g, 24 ml, 0.75 mole) added dropwise to the hot mixture. After completing the addition, the mixture was poured onto water (600 ml) and a solid filtered off and air dried to afford 3,4-diphenyl-1H-pyrazole (52.18 g, 92%) which was used without further purification. An analytical sample was prepared by recrystallization from ethanol; m.p.=150°-152° C. (lit. m.p.=154°-155° C.).

Workup

  1. customAfter 30 minutes the heating source was removed
  2. additionthe addition
  3. additionthe mixture was poured onto water (600 ml)
  4. filtrationa solid filtered off
  5. customair dried

Sources & evidence

ORD record
ord-3cd9a24681a94620a83d8f819754f656
Source dataset
uspto-grants-1991_12
Patent number
US05071866

Reaction notes

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