Sodium hydride → (S)-tert-butyl 2-(6-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate

HRID 625568Notes

Reaction equation

HRID 625568 reaction equation
[H-].[Na+].[Br:3][C:4]1[N:9]=[C:8]2[NH:10][C:11]([C@@H:13]3[CH2:17][CH2:16][CH2:15][N:14]3[C:18]([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19])=[N:12][C:7]2=[N:6][CH:5]=1.[CH3:25][Si:26]([CH2:29][CH2:30][O:31][CH2:32]Cl)([CH3:28])[CH3:27]>CN(C=O)C.O.CCOC(C)=O>[Br:3][C:4]1[N:9]=[C:8]2[N:10]=[C:11]([C@@H:13]3[CH2:17][CH2:16][CH2:15][N:14]3[C:18]([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19])[N:12]([CH2:32][O:31][CH2:30][CH2:29][Si:26]([CH3:28])([CH3:27])[CH3:25])[C:7]2=[N:6][CH:5]=1.[Br:3][C:4]1[N:9]=[C:8]2[N:10]([CH2:32][O:31][CH2:30][CH2:29][Si:26]([CH3:28])([CH3:27])[CH3:25])[C:11]([C@@H:13]3[CH2:17][CH2:16][CH2:15][N:14]3[C:18]([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19])=[N:12][C:7]2=[N:6][CH:5]=1

Participants

8

Reactant 3

HCID 24758Sodium hydrideHCID 27242712-Chloromethyl 2-(trimethylsilyl)ethyl etherHCID 58498842(S)-tert-butyl 2-(6-bromo-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate

Product 2

HCID 58498762(S)-tert-butyl 2-(6-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylateHCID 58498888(S)-tert-butyl 2-(5-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Procedure

A 60% dispersion of NaH (75 mg, 1.9 mmol) was added to a stirred solution of (S)-tert-butyl 2-(6-bromo-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate (627 mg, 1.70 mmol) in DMF (15 mL) and the reaction was stirred for 1.5 h at room temperature. Then SEM-Cl (0.30 mL, 1.7 mmol) was added and the reaction was stirred overnight. The reaction was diluted with water (˜30 mL) and EtOAc (˜35 mL), the layers were separated and the organic layer was washed with brine (30 mL), dried (MgSO4), filtered and concentrated. The crude yellow oil was purified by flash chromatography (40 g SiO2, 20-30% EtOAc/hexanes) to yield (S)-tert-butyl 2-(5-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate (421 mg) as a clear colorless oil and (S)-tert-butyl 2-(6-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-imidazo[4,5-b]pyrazin-2-yl)pyrrolidine-1-carboxylate (345 mg) as a clear colorless oil. The absolute regiochemistry of the SEM group was not established unambiguously, the names (and structures) may be exchanged in these intermediates.

Workup

  1. stirringthe reaction was stirred overnight
  2. customthe layers were separated
  3. washthe organic layer was washed with brine (30 mL)
  4. dry with materialdried (MgSO4)
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe crude yellow oil was purified by flash chromatography (40 g SiO2, 20-30% EtOAc/hexanes)

Sources & evidence

ORD record
ord-9d1b0109f8864e65b4cfad2411425e82
Source dataset
uspto-grants-2016_04
Patent number
US09303007B2

Reaction notes

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