1,2,3,4-Tetrahydroisoquinoline → 3,4-Dihydroisoquinoline

HRID 2036215Notes

Reaction equation

HRID 2036215 reaction equation
BrN1C(=O)CCC1=O.[CH2:9]1[C:18]2[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=2)[CH2:12][CH2:11][NH:10]1.[OH-].[Na+]>C(Cl)Cl>[CH:9]1[C:18]2[C:13](=[CH:14][CH:15]=[CH:16][CH:17]=2)[CH2:12][CH2:11][N:10]=1

Participants

5

Reactant 3

HCID 70461,2,3,4-TetrahydroisoquinolineHCID 14798Sodium HydroxideHCID 67184N-bromobutanimide

Product 1

HCID 767053,4-Dihydroisoquinoline

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

N-Bromosuccinimide (9.89 g, 55.0 mmol, 1.1 eq.) was added cautiously and portionwise over 20 min to a solution of 1,2,3,4-tetrahydroisoquinoline (6.34 mL, 50.0 mmol, 1.0 eq.) in DCM (130 mL) at r.t. The mixture was stirred at r.t. for 1.5 hour. 30% aq. NaOH (35 mL) was added and the mixture was stirred at r.t. for 2 hours. The organic layer was separated and washed with water (1×70 mL). The product was extracted with 10% aq. HCl (2×80 mL). The combined acidic extracts were washed with DCM (1×80 mL) and basified with 25% NH3. The resulting mixture was extracted with DCM (2×80 mL). The comb. org. extracts were dried over MgSO4, filtered and concentrated in vacuo to yield the 3,4-dihydroisoquinoline as an orange oil. The product was used without further purification.

Workup

  1. stirringthe mixture was stirred at r.t. for 2 hours
  2. customThe organic layer was separated
  3. washwashed with water (1×70 mL)
  4. extractionThe product was extracted with 10% aq. HCl (2×80 mL)
  5. washThe combined acidic extracts were washed with DCM (1×80 mL)
  6. extractionThe resulting mixture was extracted with DCM (2×80 mL)
  7. dry with materialextracts were dried over MgSO4
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-e883ae0af7c04f479a518a89e381ad27
Source dataset
uspto-grants-2013_11
Patent number
US08575158B2

Reaction notes

Loading…