Ethyl Acetate → 5-tosyl-5H-pyrrolo[2,3-b]pyrazine-2-carbaldehyde

HRID 1969526Notes

Reaction equation

HRID 1969526 reaction equation
[CH:1](/[C:9]1[N:10]=[C:11]2[CH:17]=[CH:16][N:15]([S:18]([C:21]3[CH:27]=[CH:26][C:24]([CH3:25])=[CH:23][CH:22]=3)(=[O:20])=[O:19])[C:12]2=[N:13][CH:14]=1)=C\C1C=CC=CC=1.I([O-])(=O)(=O)=[O:29].[Na+].[O-]S([O-])(=S)=O.[Na+].[Na+].CCOC(C)=O>O1CCOCC1.O.[Os](=O)(=O)(=O)=O>[S:18]([N:15]1[C:12]2=[N:13][CH:14]=[C:9]([CH:1]=[O:29])[N:10]=[C:11]2[CH:17]=[CH:16]1)([C:21]1[CH:27]=[CH:26][C:24]([CH3:25])=[CH:23][CH:22]=1)(=[O:20])=[O:19]

Participants

8

Reactant 4

HCID 8857Ethyl AcetateHCID 24477Sodium ThiosulfateHCID 23667635Sodium periodate2×HCID 58009875HCID 58009875, compound

Product 1

HCID 580098835-tosyl-5H-pyrrolo[2,3-b]pyrazine-2-carbaldehydeYield 80%

Reagents, catalysts & solvents 3

HCID 30318Osmium TetroxideCatalyst2×HCID 962WaterSolventHCID 312751,4-DioxaneSolvent

Procedure

To a solution of (E)-2-styryl-5-tosyl-5H-pyrrolo[2,3-b]pyrazine (1.2 g, 3.2 mmol) in 1,4-dioxane (20 mL) and water (2.0 mL) was added sodium periodate (2.73 g, 12.8 mmol) followed by osmium tetroxide (2.5 wt % in t-BuOH, 4.01 mL, 0.320 mmol). The reaction mixture was stirred for about 1 day at ambient temperature and then additional sodium periodate (2.73 g, 12.78 mmol) and osmium tetroxide (2.5 wt % in t-BuOH, 4.01 mL, 0.320 mmol) were added. After stirring for about 2 days, a solution of 10% aqueous Na2S2O3 (100 mL) and EtOAc (100 mL) was added. The organic layer was separated, dried over anhydrous Na2SO4, filtered, and coned under reduced pressure to give a solid, which was triturated with heptane to remove benzaldehyde. The resulting solid was dried in vacuo to provide 5-tosyl-5H-pyrrolo[2,3-b]pyrazine-2-carbaldehyde as a brown solid (0.77 g, 80%): LC/MS (Table 1, Method a) Rt=2.01 min; MS m/z: 334 (M+H)+.

Workup

  1. stirringAfter stirring for about 2 days
  2. customThe organic layer was separated
  3. dry with materialdried over anhydrous Na2SO4
  4. filtrationfiltered
  5. customto give a solid, which
  6. customwas triturated with heptane
  7. customto remove benzaldehyde
  8. customThe resulting solid was dried in vacuo

Sources & evidence

ORD record
ord-fe2b1b49b7ed45b3b938195d85c6c9df
Source dataset
uspto-grants-2013_04
Patent number
US08426411B2

Reaction notes

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