Potassium Carbonate → 5-Nitro-2-(2-(pyrrolidin-1-yl)ethyl)-2H-indazole

Reaction equation

Cl.Cl[CH2:3][CH2:4][N:5]1[CH2:9][CH2:8][CH2:7][CH2:6]1.C([O-])([O-])=O.[K+].[K+].[N+:16]([C:19]1[CH:20]=[C:21]2[C:25](=[CH:26][CH:27]=1)[NH:24][N:23]=[CH:22]2)([O-:18])=[O:17]>C(#N)C>[N+:16]([C:19]1[CH:27]=[CH:26][C:25]2[C:21](=[CH:22][N:23]([CH2:3][CH2:4][N:5]3[CH2:9][CH2:8][CH2:7][CH2:6]3)[N:24]=2)[CH:20]=1)([O-:18])=[O:17]

Participants

Procedure

10.5 g (62.0 mmol) 1-(2-chloroethyl)-pyrrolidine hydrochloride and 12.9 g (93.0 mmol) K2CO3 are added successively to a solution of 5.00 g (31.0 mmol) 5-nitroindazole in 100 mL acetonitrile. The reaction solution is stirred for 2 h at RT and refluxed for a further 5 h. After the solution has cooled the insoluble salts are filtered off and the solvent is eliminated i.vac. The residue is taken up in EtOAc and water. The organic phase is dried over MgSO4 and the solvent is eliminated i.vac. A 4:1 mixture of 5-nitro-1-(2-pyrrolidin-1-yl-ethyl)-1H-indazole and 5-nitro-2-(2-pyrrolidin-1-yl-ethyl)-2H-indazole is obtained. The purification is carried out by column chromatography on Alox (PE/EtOAc 3:2).