Sodium hydride → ethyl 4-(trifluoromethyl)-1H-pyrrole-3-carboxylate

HRID 649034Notes

Reaction equation

HRID 649034 reaction equation
[F:1][C:2]([F:11])([F:10])/[CH:3]=[CH:4]/[C:5]([O:7][CH2:8][CH3:9])=[O:6].S([CH2:22][N+:23]#[C-:24])(C1C=CC(C)=CC=1)(=O)=O.[H-].[Na+].[H][H]>C(O)(=O)C.O.C(OCC)C.CS(C)=O>[F:1][C:2]([F:10])([F:11])[C:3]1[C:4]([C:5]([O:7][CH2:8][CH3:9])=[O:6])=[CH:24][NH:23][CH:22]=1

Participants

9

Reactant 4

HCID 24758Sodium hydrideHCID 161915Tosylmethyl isocyanideHCID 5371261Ethyl (2E)-4,4,4-trifluoro-2-butenoateHCID 178418361HCID 178418361, compound

Product 1

HCID 14370786ethyl 4-(trifluoromethyl)-1H-pyrrole-3-carboxylateYield 72.4%

Reagents, catalysts & solvents 4

HCID 176Acetic AcidCatalystHCID 679Dimethyl SulfoxideSolventHCID 962WaterSolventHCID 3283Diethyl EtherSolvent

Conditions

Temperature
20 °C

Procedure

7.4 g of ethyl 4,4,4-trifluoro-(E)-butenoate (E. T. McBee, J. Am. Soc. Vol. 76 p. 3724 (1924)) and 8.6 g of tosylmethyl isocyanide were introduced into 200 ml of a mixture of dimethylsulfoxide and ethyl ether (1-2) and then 2.9 g of sodium hydride at 50% in vaseline were added in small portions. Hydrogen evolved and after stirring for 30 minutes at 20° C., a few drops of acetic acid were added. The mixture was poured into a mixture of water and ice and was extracted with ether. The extracts were concentrated to dryness by distilling under reduced pressure and the residue was chromatographed over silica. Eluting with a mixture of hexane and ethyl acetate (7-3) to yielded 6.6 g of ethyl 3-trifluoromethyl-1H-pyrrol-4-carboxylate melting at 165° C.

Workup

  1. extractionwas extracted with ether
  2. concentrationThe extracts were concentrated to dryness
  3. distillationby distilling under reduced pressure
  4. customthe residue was chromatographed over silica
  5. washEluting with a mixture of hexane and ethyl acetate (7-3)

Sources & evidence

ORD record
ord-60d81d11942e4598b78ad2d49edc5a96
Source dataset
uspto-grants-1988_04
Patent number
US04737513

Reaction notes

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