Propargyl bromide → 2-[(Prop-2-yn-1-yl)sulfanyl]-1H-indole

Reaction equation

[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH2:3][C:2]1=[S:10].C(=O)([O-])[O-].[K+].[K+].[CH2:17](Br)[C:18]#[CH:19]>CC(C)=O>[CH2:19]([S:10][C:2]1[NH:1][C:9]2[C:4]([CH:3]=1)=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:18]#[CH:17]

Participants

Procedure

To a solution of the product (14.9 g) of the above (1) in acetone (250 ml) are added potassium carbonate (16.5 g) and propargyl bromide (14.3 g) successively and the mixture is stirred at room temperature for three hours. The precipitate is filtered off. The filtrate is condensed and extracted with ether after addition of water. The extract is washed with water, dried and evaporated to remove the solvent yielding an oily residue (23 g). The residue is chromatographed on a column of silica gel (100 g) and eluted with benzene-hexane. The eluate is condensed to give the tile compound as an oil (18.3 g). Yield: 98%