Benzaldehyde → HCID 15700638, compound

HRID 236798Notes

Reaction equation

HRID 236798 reaction equation
[NH2:1][C:2]1[C:3]2[CH:16]=[CH:15][CH:14]=[CH:13][C:4]=2[S:5][C:6]=1[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1.[CH:17](=O)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.[BH4-].[Na+]>C(O)C.O>[CH2:17]([N:1]([CH2:2][C:3]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:4]=1)[C:2]1[C:3]2[CH:16]=[CH:15][CH:14]=[CH:13][C:4]=2[S:5][C:6]=1[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

6

Reactant 3

HCID 240BenzaldehydeHCID 4311764Sodium borohydrideHCID 12415655HCID 12415655, compound

Product 1

HCID 15700638HCID 15700638, compound

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Procedure

Preparation of the starting material a solution of 15.0 g (67 mmol) of 3-amino-2-phenyl-benzo(b)thiophene and 7.8 g (74 mmol) of benzaldehyde freshly distilled in 50 milliliters of benzene is refluxed for 10 hours with a water trap. After cooling, it is diluted with benzene, the excess benzaldehyde is eliminated by stirring with a solution of sodium bisulphite, the organic phase is dried over Na2SO4 and evaporated: 3-benzylidenamino-2-phenyl-benzo(b)thiophene in the form of a crude oily product which crystallises when it is triturated with methanol: 19.0 g (91% of theory) of yellow crystals, mp 92°-93° C. (ethanol). 9.6 g (31 mmol) of this Schiff base and 12 g (0.32 mol) of NaBH4 in 300 milliliters of absolute ethanol are refluxed with stirring for 25 hours. The cooled reaction mixture is diluted in water and extracted with ether. By evaporating the organic phase dried over K2CO3, the 3-benzylamino-2-phenyl-benzo(b)thiophene is obtained in the form of a crude oily product which crystallises when it is triturated with methanol. 9.0 g (92% of theory), colourless crystals, mp 52°-53° C. (methanol).

Workup

  1. distillationfreshly distilled in 50 milliliters of benzene
  2. temperatureis refluxed for 10 hours with a water trap
  3. temperatureAfter cooling
  4. additionit is diluted with benzene
  5. dry with materialthe organic phase is dried over Na2SO4
  6. customevaporated
  7. custom3-benzylidenamino-2-phenyl-benzo(b)thiophene in the form of a crude oily product which crystallises when it
  8. customis triturated with methanol
  9. stirringwith stirring for 25 hours
  10. customThe cooled reaction mixture
  11. extractionextracted with ether
  12. customBy evaporating the organic phase
  13. dry with materialdried over K2CO3

Sources & evidence

ORD record
ord-ee0ad9b1f50e4ad7a059fa5c3dd622d0
Source dataset
uspto-grants-1979_06
Patent number
US04157399

Reaction notes

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