Trifluoroacetic acid → N-tert-butyl-2-(5-(difluoromethoxy)-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide

HRID 246397

Reaction equation

HRID 246397 reaction equation
[C:1]([NH:5][C:6]([C:8]1[C:16]2[C:11](=[N:12][CH:13]=[C:14]([C:17]3[C:25]4[C:20](=[CH:21][CH:22]=[C:23]([O:26][CH:27]([F:29])[F:28])[CH:24]=4)[NH:19][N:18]=3)[N:15]=2)[N:10](COCC[Si](C)(C)C)[CH:9]=1)=[O:7])([CH3:4])([CH3:3])[CH3:2].C(O)(C(F)(F)F)=O>ClCCl>[C:1]([NH:5][C:6]([C:8]1[C:16]2[C:11](=[N:12][CH:13]=[C:14]([C:17]3[C:25]4[C:20](=[CH:21][CH:22]=[C:23]([O:26][CH:27]([F:29])[F:28])[CH:24]=4)[NH:19][N:18]=3)[N:15]=2)[NH:10][CH:9]=1)=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

4

Reactant 2

HCID 6422Trifluoroacetic acidHCID 712795662-(5-difluoromethoxy-1H-indazol-3-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid tert-butylamide

Product 1

HCID 71279608N-tert-butyl-2-(5-(difluoromethoxy)-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamideYield 62.7%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
25 °C

Procedure

To a pale yellow solution of N-tert-butyl-2-(5-(difluoromethoxy)-1H-indazol-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide (55 mg, 104 μmol) in dichloromethane (3 mL) was added TFA (1.48 g, 1000 μL, 13.0 mmol25), the reaction mixture turned orange and was stirred at 25° C. overnight then concentrated. The residue was re-dissolved in 5 mL of a solution of (dichloromethane/MeOH/ammonium hydroxide; 60:10:1) and stirred at 25° C. for 3 h, then evaporated to a light yellow solid, dissolved in dichloromethane (added few drops MeOH and heating) and purified by chromatography (spherical silica 20-45 μm, 23 g, Versaflash Supelco) eluting with 0 to 5% over 15 min (MeOH containing 10% ammonium hydroxide)/dichloromethane. The pure product suspended in dichloromethane and cyclohexane added to complete solid formation, solid was separated by decantation and dried under high vacuum to give N-tert-butyl-2-(5-(difluoromethoxy)-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide (26 mg, 64.9 μmol, 62.7%) as a white solid. MS (M+H)+=401.1 (100% purity); 1H NMR (DMSO-d6) δ: 9.12 (s, 1H), 8.36 (s, 1H), 8.21 (d, J=2.3 Hz, 1H), 7.88 (s, 1H), 7.72 (d, J=9.1 Hz, 1H), 7.35 (dd, J=9.1, 2.3 Hz, 1H), 7.17 (t, J=74.4 Hz, 1H), 1.50 (s, 9H).

Workup

  1. concentrationthen concentrated
  2. dissolutionThe residue was re-dissolved in 5 mL of a solution of (dichloromethane/MeOH/ammonium hydroxide; 60:10:1)
  3. stirringstirred at 25° C. for 3 h
  4. customevaporated to a light yellow solid
  5. dissolutiondissolved in dichloromethane (added few drops MeOH and heating)
  6. custompurified by chromatography (spherical silica 20-45 μm, 23 g, Versaflash Supelco)
  7. washeluting with 0 to 5% over 15 min (MeOH containing 10% ammonium hydroxide)/dichloromethane
  8. additioncyclohexane added
  9. customwas separated by decantation
  10. customdried under high vacuum

Sources & evidence

ORD record
ord-637855607fc7431eb47eebb80abceabb
Source dataset
uspto-grants-2014_02
Patent number
US08658646B2

Linked notes

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