Dimethylformamide → Methyl 3-cyano-1H-indazole-5-carboxylate
Reaction equation
Br[C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][N:6]=[C:5]2[C:11]#[N:12].[C:13]([O-:16])(=[O:15])C.[Na+].[CH3:18]N(C)C=O>CO.C1(P(C2C=CC=CC=2)[C-]2C=CC=C2)C=CC=CC=1.[C-]1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=C1.[Fe+2].[Pd](Cl)Cl>[C:11]([C:5]1[C:4]2[C:8](=[CH:9][CH:10]=[C:2]([C:13]([O:16][CH3:18])=[O:15])[CH:3]=2)[NH:7][N:6]=1)#[N:12]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 2
Procedure
A suspension of 5-bromo-3-cyanoindazole (3 g, 13.51 mmol), palladium dichloride 1,1′-bis(diphenylphosphino)ferrocene (1.76 g, 2.16 mmol), sodium acetate (3.32 g, 40.5 mmol), dimethylformamide (1 mL) in methanol (100 mL) was degassed, and kept under carbon monoxide (80 psi) pressure at 80° C. in a autoclave for 16 hours. The mixture was diluted with water (50 mL), filtered through Celite® bed and the filtrate was concentrated. The obtained residue was acidified with 10% citric acid solution and extracted with ethyl acetate (2×100 mL). The combined organic layers were washed with brine (50 mL), dried over anhydrous sodium sulfate and concentrated. The obtained crude product was purified by column chromatography (100-200 mesh silica gel) using 10% ethyl acetate in chloroform as eluent to afford methyl 3-cyano-1H-indazole-5-carboxylate (1.8 g, 68%) as a solid. 1HNMR (CDCl3) δ ppm 10.8 (s, 1H), 8.7 (s, 1H), 8.22 (d, 1H), 7.64 (d, 1H), 4.0 (s, 3H).
Workup
- customwas degassed
- customat 80° C.
- customfor 16 hours
- additionThe mixture was diluted with water (50 mL)
- filtrationfiltered through Celite® bed
- concentrationthe filtrate was concentrated
- extractionextracted with ethyl acetate (2×100 mL)
- washThe combined organic layers were washed with brine (50 mL)
- dry with materialdried over anhydrous sodium sulfate
- concentrationconcentrated
- customThe obtained crude product
- customwas purified by column chromatography (100-200 mesh silica gel)
Sources & evidence
- ORD record
- ord-3c948cdbc25c41698c64af4ef581f4d3
- Source dataset
- uspto-grants-2012_10
- Patent number
- US08288405B2
Reaction notes
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