Hydrochloric Acid → 4-(4-Bromo-1H-pyrazol-1-yl)piperidine

HRID 216722Notes

Reaction equation

HRID 216722 reaction equation
Cl.O1CCOCC1.C(OC([N:15]1[CH2:20][CH2:19][CH:18]([N:21]2[CH:25]=[C:24]([Br:26])[CH:23]=[N:22]2)[CH2:17][CH2:16]1)=O)(C)(C)C>C(Cl)Cl>[Br:26][C:24]1[CH:23]=[N:22][N:21]([CH:18]2[CH2:19][CH2:20][NH:15][CH2:16][CH2:17]2)[CH:25]=1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 312751,4-DioxaneHCID 45480278tert-Butyl 4-(4-bromo-1H-pyrazol-1-yl)piperidine-1-carboxylate

Product 1

HCID 521916214-(4-Bromo-1H-pyrazol-1-yl)piperidine

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A 4 M solution of HCl in 1,4-dioxane (13.5 ml, 54 mmol) is added to a solution of 4-(4-Bromo-pyrazol-1-yl)-piperidine-1-carboxylic acid tert-butyl ester (as obtained in preparation 62, 5.92 g, 17.94 mmol) in CH2Cl2 (50 ml) and the reaction mixture is stirred at RT for 6 h. The suspension is filtered on a Por. 4 Fritte and the cake dissolved in EtOAc. A saturated solution of NaHCO3 is added and the phases are separated. The aqueous phase is extracted 3× with EtOAc. The combined organic layers are washed with NaHCO3, brine, dried over Na2SO4, filtered and the filtrate is concentrated in vacuo. The residue is used without further purification in the next step, and afford the title compound as pale orange solid, Rt=0.582 min (Acquity HPLC BEH C18, 2.1×50 mm, 1.7 micron, detection 215 nM, 0.1 min 2% CH3CN in H2O, 2% to 100% CH3CN in H2O in 1.5 min, 0.4 min 100% CH3CN+0.1% TFA, flow rate 1.0 ml/min); MS: 330 (M+1, 79Br)+

Workup

  1. filtrationThe suspension is filtered on a Por
  2. dissolution4 Fritte and the cake dissolved in EtOAc
  3. additionA saturated solution of NaHCO3 is added
  4. customthe phases are separated
  5. extractionThe aqueous phase is extracted 3× with EtOAc
  6. washThe combined organic layers are washed with NaHCO3, brine
  7. dry with materialdried over Na2SO4
  8. filtrationfiltered
  9. concentrationthe filtrate is concentrated in vacuo
  10. customThe residue is used without further purification in the next step

Sources & evidence

ORD record
ord-a55703ef03ff46538ea641c86aa20fe0
Source dataset
uspto-grants-2012_06
Patent number
US08193189B2

Reaction notes

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