1,2-Diiodoethane → tert-Butyl N-[7-iodo-2-methylthiopyrazolo[1,5-a]pyridin-3-yl]carbamate

HRID 347845

Reaction equation

HRID 347845 reaction equation
[CH3:1][S:2][C:3]1[C:11]([NH:12][C:13](=[O:19])[O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][N:5]2[N:4]=1.C([Li])CCC.[I:25]CCI.[Cl-].[NH4+]>O1CCCC1>[I:25][C:10]1[N:5]2[N:4]=[C:3]([S:2][CH3:1])[C:11]([NH:12][C:13](=[O:19])[O:14][C:15]([CH3:16])([CH3:18])[CH3:17])=[C:6]2[CH:7]=[CH:8][CH:9]=1

Participants

6

Reactant 4

HCID 122241,2-DiiodoethaneHCID 25517Ammonium ChlorideHCID 21984591tert-butyl N-[2-methylthiopyrazolo[1,5-a]pyridin-3-yl]carbamateHCID 178418339Butyllithium

Product 1

HCID 21984511tert-Butyl N-[7-iodo-2-methylthiopyrazolo[1,5-a]pyridin-3-yl]carbamateYield 68.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a solution of tert-butyl N-[2-methylthiopyrazolo[1,5-a]pyridin-3-yl]carbamate (21.6 g) dissolved in tetrahydrofuran (1 L) was n-butyllithium (1.6M hexane solution; 130 mL) dropwise at −78° C. under a nitrogen stream, and the reaction mixture was stirred for 30 minutes. A solution of 1,2-diiodoethane (24 g) in tetrahydrofuran (50 mL) was added to the obtained reaction mixture, and stirring was continued for 1 hour. After adding saturated aqueous ammonium chloride to the reaction mixture, the temperature was raised to room temperature, extraction was performed with ethyl acetate and the organic extract was washed with water and brine. The obtained organic extract was dried over anhydrous magnesium sulfate and filtered, the solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography and the title compound (21.5 g) was obtained as yellow crystals from the n-hexane:ethyl acetate (5:1) fraction.

Workup

  1. customdropwise at −78° C.
  2. stirringstirring
  3. waitwas continued for 1 hour
  4. extractionextraction
  5. extractionthe organic extract
  6. washwas washed with water and brine
  7. extractionThe obtained organic extract
  8. dry with materialwas dried over anhydrous magnesium sulfate
  9. filtrationfiltered
  10. customthe solvent was evaporated under reduced pressure
  11. customthe residue was purified by silica gel column chromatography

Sources & evidence

ORD record
ord-7ec69c56efe7422795afe34887b97bb3
Source dataset
uspto-grants-2007_02
Patent number
US07176216B2

Linked notes

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