Pyrrole → Sodium pyrrolide

HRID 129909Notes

Reaction equation

HRID 129909 reaction equation
[CH3:1][C:2]1[NH:3][C:4]([CH3:7])=[CH:5][CH:6]=1.[Na].[NH:9]1[CH:13]=[CH:12][CH:11]=[CH:10]1.[H-].[Na+:15].C([Al](CC)CC)C.OP(O)(O)=O.CO>C(COC)OC.O1CCCC1.CO>[CH3:1][C:2]1[N-:3][C:4]([CH3:7])=[CH:5][CH:6]=1.[Na+:15].[N-:9]1[CH:13]=[CH:12][CH:11]=[CH:10]1.[Na+:15]

Participants

11

Reactant 6

HCID 8027PyrroleHCID 122652,5-DimethylpyrroleHCID 24758Sodium hydrideHCID 83032Phosphoric acid, methyl esterHCID 5360545Sodium2×HCID 16682930Triethylaluminum

Product 2

HCID 10909487Sodium pyrrolideHCID 14591924Sodium 2,5-dimethylpyrrolide

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 8028TetrahydrofuranSolvent2×HCID 80711,2-DimethoxyethaneSolvent

Procedure

Manipulations of all reactants were carried out either in a drybox employing nitrogen, or in airless glassware employing vacuum or nitrogen. Tetrahydrofuran (THF), toluene, benzene, diethylbenzene (Aldrich, 97% mixture of 1,2-, 1,3-, 1,4- isomers) and pentane were purified by distillation over sodiumbenzophenone ketyl under nitrogen, then degassed via a nitrogen purge. Dimethoxyethane (DME) (Aldrich, anhydrous) was degasseal via nitrogen purge and used without further purification. Pyrrole (Aldrich, 98%) was vacuum distilled over sodium, then degassed via nitrogen purge. 2,5-Dimethylpyrrole was dried with calcium sulfate and vacuum distilled. Sodium 2,5-dimethylpyrrolide (NaC6H8N) was prepared by reacting 2,5-dimethylpyrrole with an excess of sodium (40% by weight dispersion in mineral spirits) in refluxing tetrahydrofuran under nitrogen. Sodium pyrrolide was prepared by reacting pyrrole with an equivalent molar amount (1:1) of NaH (Aldrich, 60% by weight in mineral oil) or sodium (40% dispersion by weight in mineral spirits) in dimethoxyethane or tetrahydrofuran (THF) at ambient temperature under nitrogen. Triethylaluminum (TEA) (Adrich 1.0M, hexanes and 1.9M toluene) was used as received. Ketjen Grade B alumina (Al2O3) and Davison 952 silica (SiO2) were the commercial materials used as supports for catalyst preparations. Fluorided-alumina (F/Al2O3, 15 wt % F) was prepared by the addition of a solution of NH4HF2 in methanol to Ketjen Grade B alumina. Phosphated silica (P/SiO2, P/Si molar ratio=0.1) was prepared by the addition of a 10% H3PO4 /methanol solution to Davison 952 silica. The aluminophosphate (AlPO4) used in the following experiments was made as described in McDaniel et al, U.S. Pat. No. 4,364,855 (1982). The supports were activated by placing up to 25 g into a fritted quartz tube, fluidizing with air and calcining at 700° C., except for P/SiO2 at 350° C., for 3 hours. The air stream was switched to nitrogen until the support cooled to ambient temperature.

Workup

  1. distillationTetrahydrofuran (THF), toluene, benzene, diethylbenzene (Aldrich, 97% mixture of 1,2-, 1,3-, 1,4- isomers) and pentane were purified by distillation over sodiumbenzophenone ketyl under nitrogen
  2. customdegassed via a nitrogen
  3. custompurge
  4. custompurge
  5. customused without further purification
  6. distillationdistilled over sodium
  7. customdegassed via nitrogen
  8. custompurge
  9. dry with material2,5-Dimethylpyrrole was dried with calcium sulfate and vacuum
  10. distillationdistilled
  11. customat ambient temperature
  12. customby placing up to 25 g into a fritted quartz tube

Sources & evidence

ORD record
ord-0c059e59f7584cd995af467204f76460
Source dataset
uspto-grants-1995_11
Patent number
US05470926

Reaction notes

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