Chlorosulfonyl isocyanate → 3-Cyano-1-cyclopropyl-6-methoxyindole
Reaction equation
[CH:1]1([N:4]2[C:12]3[C:7](=[CH:8][CH:9]=[C:10]([O:13][CH3:14])[CH:11]=3)[CH:6]=[CH:5]2)[CH2:3][CH2:2]1.ClS([N:19]=[C:20]=O)(=O)=O>CN(C=O)C>[C:20]([C:6]1[C:7]2[C:12](=[CH:11][C:10]([O:13][CH3:14])=[CH:9][CH:8]=2)[N:4]([CH:1]2[CH2:3][CH2:2]2)[CH:5]=1)#[N:19]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 1-cyclopropyl-6-methoxylindole (3.29 g, 17.6 mmol) in dry DMF (30 mL), at 0° C., is added chlorosulfonyl isocyanate (3.11 g, 1.91 mL, 22.0 mmol). After the addition, the mixture is stirred at room temperature for 2 h, followed by aqueous work-up. Chromatography (silica gel, hexanes/EtOAc, 9/1) furnishes 3-cyano-1-cyclopropyl-6-methoxyindole (3.05 g, 82%).