Sodium borohydride → 5-amino-2-tert-butyl-1H-indole-7-carbonitrile

HRID 1403922Notes

Reaction equation

HRID 1403922 reaction equation
[C:1]([C:5]1[NH:6][C:7]2[C:12]([CH:13]=1)=[CH:11][C:10]([N+:14]([O-])=O)=[CH:9][C:8]=2[C:17]#[N:18])([CH3:4])([CH3:3])[CH3:2].[BH4-].[Na+]>CO>[NH2:14][C:10]1[CH:11]=[C:12]2[C:7](=[C:8]([C:17]#[N:18])[CH:9]=1)[NH:6][C:5]([C:1]([CH3:4])([CH3:3])[CH3:2])=[CH:13]2

Participants

4

Reactant 2

HCID 4311764Sodium borohydrideHCID 534211842-Tert-butyl-5-nitro-1H-indole-7-carbonitrile

Product 1

HCID 591292165-amino-2-tert-butyl-1H-indole-7-carbonitrileYield 61.2%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of crude product 2-tert-butyl-5-nitro-1H-indole-7-carbonitrile (0.87 g, 3.6 mmol) in MeOH (10 mL) was added NiCl2.6H2O (1.8 g, 7.2 mmol) at −5° C. The reaction mixture was stirred for 30 min, then NaBH4 (0.48 g, 14.32 mmol) was added to the reaction mixture at 0° C. After 5 min, the reaction mixture was quenched with water, filtered and extracted with EtOAc. The combined organic layers were dried over Na2SO4 and concentrated under vacuum to obtain the crude product, which was purified by column chromatography (5-20% EtOAc in petroleum ether) to obtain 5-amino-2-tert-butyl-1H-indol-7-carbonitrile (470 mg, 32% over two steps). 1H NMR (400 MHz, CDCl3) δ 8.25 (s, 1H), 7.06 (d, J=2.4 Hz, 1H), 6.84 (d, J=2.4 Hz, 1H), 6.14 (d, J=2.4 Hz, 1H), 3.57 (br s, 2H), 1.38 (s, 9H). MS (ESI) m/z: 214 (M+H+).

Workup

  1. waitAfter 5 min
  2. customthe reaction mixture was quenched with water
  3. filtrationfiltered
  4. extractionextracted with EtOAc
  5. dry with materialThe combined organic layers were dried over Na2SO4
  6. concentrationconcentrated under vacuum
  7. customto obtain the crude product, which
  8. customwas purified by column chromatography (5-20% EtOAc in petroleum ether)

Sources & evidence

ORD record
ord-abdd89f72ba24ee9a9cb332201b16638
Source dataset
uspto-grants-2014_12
Patent number
US08912199B2

Reaction notes

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