2,2-Diethoxyethylamine → 2,2-Dimethoxy-n-[(1-methyl-1h-benzimidazol-2-yl)methyl]ethanamine

HRID 243596

Reaction equation

HRID 243596 reaction equation
[CH3:1][N:2]1[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[N:4]=[C:3]1[CH:11]=O.[CH2:13]([O:15][CH:16]([O:19][CH2:20]C)[CH2:17][NH2:18])C.[BH3-]C#N.[Na+]>CO.C(O)(=O)C>[CH3:13][O:15][CH:16]([O:19][CH3:20])[CH2:17][NH:18][CH2:11][C:3]1[N:2]([CH3:1])[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[N:4]=1

Participants

6

Reactant 3

HCID 695242,2-DiethoxyethylamineHCID 7620841-methyl-1H-1,3-benzodiazole-2-carbaldehydeHCID 5003444Sodium cyanoborohydride

Product 1

HCID 552185252,2-Dimethoxy-n-[(1-methyl-1h-benzimidazol-2-yl)methyl]ethanamineYield 77.1%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 887MethanolSolvent

Procedure

A solution of 1-methyl-2-formylbenzimidazole (1 g) in methanol (27 mL) and acetic acid (0.54 mL) was treated with aminoacetaldehyde diethylacetal (0.9 g, 1 equivalent) and NaCNBH3 (0.85 g, 2 equivalents) at 25° C., stirred for 1 hour. The mixture was partitioned between water and ethyl acetate. The organic layer was separated, washed sequentially with saturated NaHCO3 and brine, and concentrated. The residue was chromatographed on silica gel, eluting with 8% methanol/dichloromethane to give 1.2 g (64%) of the title compound.

Workup

  1. customThe mixture was partitioned between water and ethyl acetate
  2. customThe organic layer was separated
  3. washwashed sequentially with saturated NaHCO3 and brine
  4. concentrationconcentrated
  5. customThe residue was chromatographed on silica gel
  6. washeluting with 8% methanol/dichloromethane

Sources & evidence

ORD record
ord-db2da2aa8b40492b8124c8489d2a059f
Source dataset
uspto-grants-2014_02
Patent number
US08653141B2

Linked notes

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