Formaldehyde → 1-(5-Bromo-4-nitro-2-thienyl)ethan-1-one

HRID 1902891Notes

Reaction equation

HRID 1902891 reaction equation
[Br:1][C:2]1[S:3][C:4]([C:7](=NO)[CH3:8])=[CH:5][CH:6]=1.[N+:11]([O-])([OH:13])=[O:12].C=[O:16].O>S(=O)(=O)(O)O>[Br:1][C:2]1[S:3][C:4]([C:7](=[O:16])[CH3:8])=[CH:5][C:6]=1[N+:11]([O-:13])=[O:12]

Participants

6

Reactant 4

HCID 712Formaldehyde2×HCID 944Nitric AcidHCID 962WaterHCID 3510072HCID 3510072, compound

Product 1

HCID 5406471-(5-Bromo-4-nitro-2-thienyl)ethan-1-one

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent2×

Procedure

2-Bromo-5-acetyl thiophene oxime (35.2 g) (0.16 mole) was dissolved in concentrated sulphuric acid (80 ml) at 5°-10° C. A mixture of fuming nitric acid (95-98%) (10.6 g) (0.16 mole) in concentrated sulphuric acid (10 ml) was added dropwise at less than 10° C. The temperature, after the addition, was allowed to rise to room temperature and the system stirred there for 60 minutes. Paraformaldehyde (2.0 g) was then added carefully and the mixture stirred at room temperature for 15 minutes. This was followed by the addition of a further amount (15.0 g) of paraformaldehyde at about 20°-26° C. Stirring was continued at this temperature for 2-3 hours further, and then the mixture was drowned into water, stirred for 30 minutes and filtered. The solid 2-bromo-3-nitro-5-acetyl thiophene was washed with water and dried. The yield was 35.3 g (88.25%).

Workup

  1. additionwas added dropwise at less than 10° C
  2. additionThe temperature, after the addition
  3. customto rise to room temperature
  4. stirringthe mixture stirred at room temperature for 15 minutes
  5. stirringStirring
  6. waitwas continued at this temperature for 2-3 hours
  7. stirringstirred for 30 minutes
  8. filtrationfiltered
  9. washThe solid 2-bromo-3-nitro-5-acetyl thiophene was washed with water
  10. customdried

Sources & evidence

ORD record
ord-5a3ef3efe988437d81ba302cf75c2967
Source dataset
uspto-grants-1982_12
Patent number
US04366321

Reaction notes

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