Sodium borohydride → HCID 46205163, compound

HRID 899581Notes

Reaction equation

HRID 899581 reaction equation
[CH3:1][Si:2]([CH3:19])([CH3:18])[CH2:3][CH2:4][O:5][CH2:6][N:7]1[C:11]2[CH:12]=[CH:13][CH:14]=[CH:15][C:10]=2[N:9]=[C:8]1[CH:16]=O.[NH2:20][CH:21]1[C:30]2[N:29]=[CH:28][CH:27]=[CH:26][C:25]=2[CH2:24][CH2:23][CH2:22]1.[BH4-].[Na+]>CO>[CH3:1][Si:2]([CH3:19])([CH3:18])[CH2:3][CH2:4][O:5][CH2:6][N:7]1[C:11]2[CH:12]=[CH:13][CH:14]=[CH:15][C:10]=2[N:9]=[C:8]1[CH2:16][NH:20][CH:21]1[C:30]2[N:29]=[CH:28][CH:27]=[CH:26][C:25]=2[CH2:24][CH2:23][CH2:22]1

Participants

5

Reactant 3

HCID 4311764Sodium borohydrideHCID 113555648-Amino-5,6,7,8-tetrahydroquinolineHCID 120171281-(2-Trimethylsilylethoxymethyl)-2-formyl-benzimidazole

Product 1

HCID 46205163HCID 46205163, compoundYield 98%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

To a stirred solution of 1-(2-trimethylsilylethoxymethyl)-2-formyl-benzimidazole (4.26 g, 15.4 mmol) in dry MeOH (50 mL) was added a solution of 8-amino-5,6,7,8-tetrahydroquinoline (2.20 g, 14.8 mmol) in dry MeOH (20 mL) and the mixture stirred for 2 h at room temperature under an argon atmosphere. The reaction mixture was concentrated under reduced pressure and the resultant residue analyzed by 1H NMR to confirm imine formation. The residue was re-dissolved in dry MeOH (80 mL) and to the resultant solution was added sodium borohydride (1.17 g, 30.8 mmol). The mixture was stirred for 5 h, concentrated in vacuo and diluted with CH2Cl2 (100 mL) and saturated aqueous NaHCO3 (125 mL). The phases were separated and the aqueous layer was extracted with CH2Cl2 (2×75 mL). The combined organic extracts were dried (Na2SO4), filtered and concentrated in vacuo. Purification of the crude material through a plug of silica gel (CH2Cl2/MeOH 96:4) afforded the desired amine (5.91 g, 98%) as an orange oil. 1H NMR (CDCl3) δ −0.07 (s, 9H), 0.90 (t, 2H, J=9 Hz), 1.72-1.83 (m, 2H), 1.95-2.01 (m, 1H), 2.76-2.85 (m, 2H), 3.54 (t, 2H, J=9 Hz), 4.33 (m, 2H), 5.68 (d, 1H, J=12 Hz), 5.75 (d, 1H, J=12 Hz), 7.05-7.09 (m, 1H), 7.25-7.30 (m, 2H), 7.38 (d, 1H, J=9 Hz), 7.44-7.46 (m, 1H), 7.71-7.73 (m, 1H), 8.36-8.38 (m, 1H).

Workup

  1. concentrationThe reaction mixture was concentrated under reduced pressure
  2. dissolutionThe residue was re-dissolved in dry MeOH (80 mL) and to the resultant solution
  3. stirringThe mixture was stirred for 5 h
  4. concentrationconcentrated in vacuo
  5. additiondiluted with CH2Cl2 (100 mL) and saturated aqueous NaHCO3 (125 mL)
  6. customThe phases were separated
  7. extractionthe aqueous layer was extracted with CH2Cl2 (2×75 mL)
  8. dry with materialThe combined organic extracts were dried (Na2SO4)
  9. filtrationfiltered
  10. concentrationconcentrated in vacuo
  11. customPurification of the crude material through a plug of silica gel (CH2Cl2/MeOH 96:4)

Sources & evidence

ORD record
ord-0f40133a9be74769af8204d8f0e58273
Source dataset
uspto-grants-2008_04
Patent number
US07354932B2

Reaction notes

Loading…