Pyridine N-Oxide → Ethyl 5-oxopentanoate

HRID 231002

Reaction equation

HRID 231002 reaction equation
Br[CH2:2][CH2:3][CH2:4][CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7].C(=O)(O)[O-:12].[Na+].[N+]1([O-])C=CC=CC=1>C1(C)C=CC=CC=1>[O:12]=[CH:2][CH2:3][CH2:4][CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7]

Participants

5

Reactant 3

HCID 12753Pyridine N-OxideHCID 84580Ethyl 5-bromovalerateHCID 516892Sodium Bicarbonate

Product 1

HCID 11137279Ethyl 5-oxopentanoateYield 48.7%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

Ethyl 5-bromopentanoate (42 g), sodium bicarbonate (34 g) and pyridine N-oxide (38 g) in toluene (250 ml) are heated together under reflux in an atmosphere of nitrogen with vigorous stirring for 9 hours. After cooling, the product is partitioned with water (400 ml). The toluene layer is separated and the aqueous layer is extracted with a further amount of toluene (100 ml). The combined toluene extracts are dried over magnesium sulphate and the toluene removed by fractional distillation. The residue is distilled under vacuum to give ethyl 5-oxopentanoate as a colourless oil (14.1 g), m.s. M+ 144.

Workup

  1. temperatureunder reflux in an atmosphere of nitrogen
  2. temperatureAfter cooling
  3. customthe product is partitioned with water (400 ml)
  4. customThe toluene layer is separated
  5. extractionthe aqueous layer is extracted with a further amount of toluene (100 ml)
  6. dry with materialThe combined toluene extracts are dried over magnesium sulphate
  7. customthe toluene removed by fractional distillation
  8. distillationThe residue is distilled under vacuum

Sources & evidence

ORD record
ord-a6783c418acf471d9a51e7869037a386
Source dataset
uspto-grants-1989_07
Patent number
US04844892

Linked notes

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