Reaction #1616366

Reaction equation

NaHSO3

iodine

N-methoxy-N-methyl-1H-indazole-3-carboxamide

bis(trifluoroacetoxy)iodobenzene

→

5-iodo-N-methoxy-N-methyl-1H-indazole-3-carboxamide

Yield 72.0%

Solvents

DCM

Conditions

Workup

1. 1
   Otherto precipitate which
2. 2
   Filtrationwas filtered
3. 3
   Washrinsed with excess DCM
4. 4
   WashThe filtrate was washed with brine
5. 5
   Dryingdried over MgSO4
6. 6
   Concentrationconcentrated
7. 7
   Otherthe remaining solid was triturated with a minimal amount of DCM
8. 8
   DryingThe combined solids were dried under vacuum over KOH

Procedure

To the N-methoxy-N-methyl-1H-indazole-3-carboxamide (IX) (20 g, 97.4 mmol) in 1 L DCM was added bis(trifluoroacetoxy)iodobenzene (46 g, 107 mmol) followed by portionwise addition of iodine (14.84 g, 58.5 mmol) at r.t. After 1 hour, 600 mL of saturated NaHSO3 was added and a solid began to precipitate which was filtered and rinsed with excess DCM. The filtrate was washed with brine, dried over MgSO4, concentrated and the remaining solid was triturated with a minimal amount of DCM. The combined solids were dried under vacuum over KOH to produce 5-iodo-N-methoxy-N-methyl-1H-indazole-3-carboxamide (X) as a white solid (23.2 g, 70 mmol, 72% yield). 1H NMR (DMSO-d6) δ ppm 3.45 (s, 4H), 3.77 (s, 4H), 7.45-7.54 (m, 1H), 7.66 (dd, J=−8.81, 1.51 Hz, 1H), 8.40 (d, J=1.01 Hz, 1H); ESIMS found for C10H10IN3O2 m/z 331 (M+H).

Source