Sodium cyanoborohydride → 5-Bromo-2-methyl-8-nitro-1,2,3,4-tetrahydroisoquinoline

HRID 641924Notes

Reaction equation

HRID 641924 reaction equation
[I-].[Br:2][C:3]1[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[C:9]2[C:4]=1[CH:5]=[CH:6][N+:7]([CH3:16])=[CH:8]2.[BH3-]C#N.[Na+]>CO>[Br:2][C:3]1[CH:12]=[CH:11][C:10]([N+:13]([O-:15])=[O:14])=[C:9]2[C:4]=1[CH2:5][CH2:6][N:7]([CH3:16])[CH2:8]2

Participants

4

Reactant 2

HCID 5003444Sodium cyanoborohydrideHCID 534463325-Bromo-2-methyl-8-nitroisoquinolin-2-ium iodide

Product 1

HCID 100160105-Bromo-2-methyl-8-nitro-1,2,3,4-tetrahydroisoquinoline

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

Into a 500 mL 3-necked round bottom flask was placed a solution of Ni(NO3)2.6H2O (12.6 g, 43.33 mmol) in CH3OH (200 mL). To the mixture was added 5-bromo-8-nitro-N-methylisoquinolinium iodide (33.33 g, 84.38 mmol). To the above was added NaCNBH3 (10.6 g, 168.68 mmol) in several batches. The resulting solution was allowed to react, with stirring, for 5 hours while the temperature was maintained at room temperature. The reaction progress was monitored by TLC (ethyl acetate/petroleum ether=1:5). The resulting solution was concentrated by evaporation under vacuum using a rotary evaporator. The residue was dissolved with 800 mL of H2O. Adjustment of the pH to 8-10 was accomplished by the addition of NaOH (5%). A filtration was performed. The resulting solution was extracted 2 times with 800 mL of ethyl acetate and the organic layers combined and dried over Na2SO4. The residue was purified by eluting through a column with a 1:5 ethyl acetate/petroleum ether solvent system. This resulted in 19.3 g (83%) of 5-bromo-2-methyl-8-nitro-1,2,3,4-tetrahydroisoquinoline as a yellow solid.

Workup

  1. customInto a 500 mL 3-necked round bottom flask was placed
  2. customto react
  3. concentrationThe resulting solution was concentrated by evaporation under vacuum
  4. customa rotary evaporator
  5. dissolutionThe residue was dissolved with 800 mL of H2O
  6. additionAdjustment of the pH to 8-10 was accomplished by the addition of NaOH (5%)
  7. filtrationA filtration
  8. extractionThe resulting solution was extracted 2 times with 800 mL of ethyl acetate
  9. dry with materialdried over Na2SO4
  10. customThe residue was purified
  11. washby eluting through a column with a 1:5 ethyl acetate/petroleum ether solvent system
  12. customThis resulted in 19.3 g (83%) of 5-bromo-2-methyl-8-nitro-1,2,3,4-tetrahydroisoquinoline as a yellow solid

Sources & evidence

ORD record
ord-98862454c35b4b1a85c8eb5583f5cada
Source dataset
uspto-grants-2010_04
Patent number
US07696229B2

Reaction notes

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