Loratadine → Desloratadine

HRID 2229805Notes

Reaction equation

HRID 2229805 reaction equation
[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[C:15](=[C:16]3[CH2:21][CH2:20][N:19](C(OCC)=O)[CH2:18][CH2:17]3)[C:10]3=[N:11][CH:12]=[CH:13][CH:14]=[C:9]3[CH2:8][CH2:7][C:6]=2[CH:27]=1>[OH-].[K+].C(O)C>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]2[C:15](=[C:16]3[CH2:17][CH2:18][NH:19][CH2:20][CH2:21]3)[C:10]3=[N:11][CH:12]=[CH:13][CH:14]=[C:9]3[CH2:8][CH2:7][C:6]=2[CH:27]=1

Participants

4

Reactant 1

HCID 3957Loratadine

Product 1

HCID 124087Desloratadine

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 14797Potassium HydroxideSolvent

Procedure

8-Chloro-6,11-dihydro-11-(1-ethoxycarbonyl-4-piperidylidene)-5H-benzo[5,6]cyclohepta[1,2-b]pyridine (prepare as described in Schumacher, D. P.; et.al., J. Org. Chem. 1989, 54, 2242-4) (2 mmols) in 13% aq. KOH (20 mL) and ethanol (20 mL) is stirred and heated at reflux temperature under argon for 24 hours. The reaction mixture is cooled and extracted with ether. The ether extracts are dried (Na2SO4), filtered and concentrated under reduced pressure to give the crude product. Pure 8-chloro-6,11-dihydro-11-(4-piperidylidene)-5H-benzo[5,6]cyclohepta[1,2-b]pyridine 8 is obtained by chromatography of the crude product.

Workup

  1. temperatureheated
  2. temperatureat reflux temperature under argon for 24 hours
  3. temperatureThe reaction mixture is cooled
  4. extractionextracted with ether
  5. dry with materialThe ether extracts are dried (Na2SO4)
  6. filtrationfiltered
  7. concentrationconcentrated under reduced pressure
  8. customto give the crude product

Sources & evidence

ORD record
ord-58b23a026c344cf1aeb062dd8f778587
Source dataset
uspto-grants-2002_07
Patent number
US06420560B1

Reaction notes

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