Trifluoroacetic acid → HCID 19367180, compound

HRID 1457766Notes

Reaction equation

HRID 1457766 reaction equation
FC(F)(F)C(O)=O.C(OC([N:15]1[CH2:20][CH2:19][CH2:18][CH2:17][CH:16]1[CH2:21][CH:22]=[CH:23][C:24]1[CH:29]=[CH:28][CH:27]=[C:26]([Cl:30])[CH:25]=1)=O)(C)(C)C>>[Cl:30][C:26]1[CH:25]=[C:24]([CH:29]=[CH:28][CH:27]=1)/[CH:23]=[CH:22]/[CH2:21][CH:16]1[CH2:17][CH2:18][CH2:19][CH2:20][NH:15]1

Participants

3

Reactant 2

HCID 6422Trifluoroacetic acidHCID 54155231HCID 54155231, compound

Product 1

HCID 19367180HCID 19367180, compoundYield 24%

Procedure

Stage b) Deprotection with trifluoroacetic acid is carried out according to the method of Preparation 2A, Stage b). The product obtained is a mixture of the Z and E isomers. Elution with a 90:10 v/v mixture of methylene chloride and 10% ammoniacal methanol by the Chromatoflash technique on silica furnishes the E isomer in the most polar fractions. The intermediate fractions are chromatographed a second time under the same conditions. All of the fractions with a high E-isomer content are combined, and, as described with regard to Preparation 2B, Stage b), are converted to the hydrochloride, which is recrystallized in isopropanol, then treated in an alkaline medium, extracted with ether and concentrated to furnish (E)-2-(m-chlorocinnamyl)piperidine with a yield of 24%.

Workup

  1. customThe product obtained
  2. additiona mixture of the Z and E isomers
  3. washElution
  4. additionwith a 90:10 v/v mixture of methylene chloride and 10% ammoniacal methanol by the Chromatoflash technique on silica
  5. customfurnishes the E isomer in the most polar fractions
  6. customThe intermediate fractions are chromatographed a second time under the same conditions
  7. customas described with regard to Preparation 2B, Stage b),
  8. customis recrystallized in isopropanol
  9. additiontreated in an alkaline medium
  10. extractionextracted with ether
  11. concentrationconcentrated

Sources & evidence

ORD record
ord-2cb53489eed340acbae5748e9f60abd5
Source dataset
uspto-grants-1998_12
Patent number
US05849760

Reaction notes

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