Sodium hydride → methyl 4-formyl-1H-pyrrole-2-carboxylate

HRID 601791Notes

Reaction equation

HRID 601791 reaction equation
[H-].[Na+].[Br-].[C:4]([O:8]C(C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)=O)(C)(C)C.C([C:33]1[NH:37][C:36]([C:38]([O:40][CH3:41])=[O:39])=[CH:35][CH:34]=1)=O>C1COCC1>[CH:4]([C:34]1[CH:35]=[C:36]([C:38]([O:40][CH3:41])=[O:39])[NH:37][CH:33]=1)=[O:8]

Participants

5

Reactant 3

HCID 24758Sodium hydrideHCID 316531methyl 5-formyl-1H-pyrrole-2-carboxylateHCID 2733853(tert-Butoxycarbonylmethyl)triphenylphosphonium Bromide

Product 1

HCID 640310methyl 4-formyl-1H-pyrrole-2-carboxylate

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a suspension of NaH (5.74 g, 143.5 mmol; 60% in oil) in THF (200 mL) at 0° C. was added (tert-butoxycarbonylmethyl)triphenylphosphonium bromide (66 g, 143.5 mmol) as a solid in three portions. Cooling was removed and the mixture was stirred at rt for 30 min. It was then cooled to 0° C. and methyl 5-formyl-1H-pyrrole-2-carboxylate (16.9 g, 110.4 mmol) in THF (60 mL) was added dropwise over 40 min. The reaction mixture was allowed to warm to rt and was stirred overnight. Silica was added and the solvent was removed. The crude product was purified by flash chromatography (0-20% EtOAc/Heptane) to afford two isomeric compounds:

Workup

  1. temperatureCooling
  2. customwas removed
  3. temperatureIt was then cooled to 0° C.
  4. temperatureto warm to rt
  5. stirringwas stirred overnight
  6. additionSilica was added
  7. customthe solvent was removed
  8. customThe crude product was purified by flash chromatography (0-20% EtOAc/Heptane)
  9. customto afford two isomeric compounds

Sources & evidence

ORD record
ord-d65970e3745d4b2fbb6552d84552b6e4
Source dataset
uspto-grants-2011_03
Patent number
US07902252B2

Reaction notes

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