Acetic Acid → N-ethyl-5-bromo-8-nitrotetrahydroisoquinoline

HRID 48209

Reaction equation

HRID 48209 reaction equation
[Br:1][C:2]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[C:8]2[C:3]=1[CH:4]=[CH:5][N:6]=[CH:7]2.[BH4-].[Na+].[C:17](O)(=O)[CH3:18]>C1COCC1>[CH2:17]([N:6]1[CH2:5][CH2:4][CH:3]2[C:8](=[C:9]([N+:12]([O-:14])=[O:13])[CH:10]=[CH:11][CH:2]2[Br:1])[CH2:7]1)[CH3:18]

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 8169835-Bromo-8-nitroisoquinolineHCID 4311764Sodium borohydride2×

Product 1

HCID 69895026N-ethyl-5-bromo-8-nitrotetrahydroisoquinolineYield 70%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of 5-bromo-8-nitroisoquinoline (1 g, 3.95 mmol) in 20 mL THF was cooled to 0° C. and treated sequentially with sodium borohydride (0.75 g, 19.83 mmol) followed by the slow addition of acetic acid (20 mL). The reaction mixture was allowed to warm to room temperature, and an additional 2 equiv. of sodium borohydride was added. After quenching with water and treatment with sodium hydroxide solution to make basic, the reaction mixture was extracted with ethyl acetate. The organic residue was chromatographed on silica gel (25% ethyl acetate in hexane) to give the N-ethyl-5-bromo-8-nitrotetrahydroisoquinoline (0.8 g, 70% yield).

Workup

  1. customAfter quenching with water and treatment with sodium hydroxide solution
  2. extractionthe reaction mixture was extracted with ethyl acetate
  3. customThe organic residue was chromatographed on silica gel (25% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-14bfbef9101f44bfbc8c35dd9bfd29e6
Source dataset
uspto-grants-2004_03
Patent number
US06703391B2

Linked notes

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