(4-Chlorophenyl)hydrazine → 2-(4-chlorophenyl)-4,4a, 5,6-tetrahydrothieno[2',3':2,3]thiopyrano[4,5-c]pyridazin-3(2H)-one

HRID 1681828Notes

Reaction equation

HRID 1681828 reaction equation
O=[C:2]1[CH:8]([CH2:9][C:10]([OH:12])=O)[CH2:7]C[S:5][C:4]2[S:13][CH:14]=[CH:15][C:3]1=2.[Cl:16][C:17]1[CH:22]=[CH:21][C:20]([NH:23][NH2:24])=[CH:19][CH:18]=1>C(O)C>[Cl:16][C:17]1[CH:22]=[CH:21][C:20]([N:23]2[C:10](=[O:12])[CH2:9][CH:8]3[CH2:7][S:5][C:4]4[S:13][CH:14]=[CH:15][C:3]=4[C:2]3=[N:24]2)=[CH:19][CH:18]=1

Participants

4

Reactant 2

HCID 70624(4-Chlorophenyl)hydrazineHCID 106339284-Oxo-4,5,6,7-tetrahydrothieno[2,3-b]thiepin-5-acetic acid

Product 1

HCID 190167892-(4-chlorophenyl)-4,4a, 5,6-tetrahydrothieno[2',3':2,3]thiopyrano[4,5-c]pyridazin-3(2H)-oneYield 33.2%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of 3.7 g of 4-oxo-4,5,6,7-tetrahydrothieno[2,3-b]thiepin-5-acetic acid and 2.6 g of 4-chlorophenylhydrazine in 50 ml of ethanol is refluxed under heating for 6.5 hours. Then, the reaction mixture is concentrated under reduced pressure. The resulting residue is dissolved in 40 ml of acetic acid and the mixture is further refluxed under heating for 1.5 hours. After cooling, the mixture is concentrated under reduced pressure, and the residue is subjected to column chromatography on silica gel and eluted with chloroform. The crystals obtained from the fraction are recrystallized from a mixed solvent of chloroform and ethanol to give 1.7 g of 2-(4-chlorophenyl)-4,4a,5,6-tetrahydrothieno[2',3':2,3]thiopyrano[4,5-c]pyridazin-3(2H)-one as pale brown crystals, melting at 134°-135° C.

Workup

  1. temperatureis refluxed
  2. temperatureunder heating for 6.5 hours
  3. concentrationThen, the reaction mixture is concentrated under reduced pressure
  4. dissolutionThe resulting residue is dissolved in 40 ml of acetic acid
  5. temperaturethe mixture is further refluxed
  6. temperatureunder heating for 1.5 hours
  7. temperatureAfter cooling
  8. concentrationthe mixture is concentrated under reduced pressure
  9. washeluted with chloroform
  10. customThe crystals obtained from the fraction
  11. customare recrystallized from a mixed solvent of chloroform and ethanol

Sources & evidence

ORD record
ord-b05d4c7b7ee44025927e7cb0dca5703c
Source dataset
uspto-grants-1992_12
Patent number
US05175162

Reaction notes

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