Pyridine → Methyl 5-formyl-2-thiophenecarboxylate oxime

HRID 581080

Reaction equation

HRID 581080 reaction equation
[CH:1]([C:3]1[S:7][C:6]([C:8]([O:10][CH3:11])=O)=[CH:5][CH:4]=1)=[O:2].Cl.[NH2:13][OH:14].N1C=CC=CC=1>C(O)C>[CH:1]([C:3]1[S:7][C:6]([C:8](=[N:13][OH:14])[O:10][CH3:11])=[CH:5][CH:4]=1)=[O:2]

Participants

5

Reactant 3

HCID 1049PyridineHCID 443297Hydroxyamine hydrochlorideHCID 818924Methyl 5-formylthiophene-2-carboxylate

Product 1

HCID 86745040Methyl 5-formyl-2-thiophenecarboxylate oximeYield 72%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of methyl 5-formyl-2-thiophenecarboxylate, prepared according to Example 10, (6.26 g, 36.78 mmoles), hydroxylamine hydrochloride (3.07 g, 44.14 mmoles) and pyridine (3.49 g, 44.14 mmoles) in 200 ml of ethanol was refluxed for 2 hours. The ethanol was removed in vacuo, the residue dissolved in ether and washed with water. The organic layer was dried (magnesium sulfate) and evaporated to a yellow solid. Trituration with a small amount of ether furnished the title compound as a white solid (4.93 g, 72%), m.p. 164-7° C. Oxime Z:E ratio:(82:18).

Workup

  1. temperaturewas refluxed for 2 hours
  2. customThe ethanol was removed in vacuo
  3. dissolutionthe residue dissolved in ether
  4. washwashed with water
  5. dry with materialThe organic layer was dried (magnesium sulfate)
  6. customevaporated to a yellow solid

Sources & evidence

ORD record
ord-0bc24906ba494c61b7080aba5c0bf987
Source dataset
uspto-grants-1999_07
Patent number
US05919809

Linked notes

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