Cornforth reagent → (S)-1-(2-thiopheneacetyl)-3-piperidinecarboxaldehyde

HRID 432828Notes

Reaction equation

HRID 432828 reaction equation
C([C@H:3]1[CH:8]([CH2:9][OH:10])[CH2:7][CH2:6][CH2:5][N:4]1[C:11](=[O:18])[CH2:12][C:13]1[S:14][CH:15]=[CH:16][CH:17]=1)C.[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1>ClCCl>[S:14]1[CH:15]=[CH:16][CH:17]=[C:13]1[CH2:12][C:11]([N:4]1[CH2:5][CH2:6][CH2:7][C@H:8]([CH:9]=[O:10])[CH2:3]1)=[O:18]

Participants

4

Reactant 2

HCID 2724130Cornforth reagentHCID 86759306(S)-ethyl 1-(2-thiopheneacetyl)-3-hydroxymethylpiperidine

Product 1

HCID 28271707(S)-1-(2-thiopheneacetyl)-3-piperidinecarboxaldehydeYield 32.6%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

(S)-ethyl 1-(2-thiopheneacetyl)-3-hydroxymethylpiperidine (180.4 ml; 0.75 mmol) was dissolved in dichloromethane (20 ml). Crushed molecular sieves (0.25 g), and commercially available pyridinium dichromate (331.2 mg; 0.88 mmol) were added and the mixture was allowed to stir at ambient temperature for 5 hours. The mixture was then filtered through celite, washed with decolorizing carbon, filtered again and then evaporated under reduced pressure at ambient temperature. Crude product was purified by distillation at approximately 250° C./0.1 torr, giving (S)-1-(2-thiopheneacetyl)-3-piperidinecarboxaldehyde (58 mg) as a thick colorless oil. MS m/z (positive ion) 317 (25), 238 (MH+; 100).

Workup

  1. additionwere added
  2. filtrationThe mixture was then filtered through celite
  3. washwashed with decolorizing carbon
  4. filtrationfiltered again
  5. customevaporated under reduced pressure at ambient temperature
  6. distillationCrude product was purified by distillation at approximately 250° C./0.1 torr

Sources & evidence

ORD record
ord-371169213b284b818385f33124448ed9
Source dataset
uspto-grants-2003_12
Patent number
US06664271B1

Reaction notes

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