Potassium Carbonate → 2-(4-Hydroxy-2-butynylthio)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+].Cl[CH2:18][C:19]#[C:20][CH2:21][OH:22]>CC(C)=O>[OH:22][CH2:21][C:20]#[C:19][CH2:18][S:10][C:2]1[NH:1][C:9]2[C:4]([CH:3]=1)=[CH:5][CH:6]=[CH:7][CH:8]=2

Participants

Procedure

To a solution of 2-indolinthione (7.45 g) in acetone (75 ml) is added potassium carbonate (7.60 g). After stirring, 4-chloro-2-butyn-1-ol (5.48 g) is added thereto. The mixture is stirred at room temperature for 5 hours and filtered. The filtrate is condensed to remove the acetone completely. The residue is dissolved into diethylamine (10 ml), kept at room temperature for 1 hour and evaporated to remove the diethylamine aiming to remove excessive agents. The residue is dissolved in ether (250 ml), washed with water, 2 N hydrochloric acid, water and a saturated saline solution successively, dried and evaporated to give the title compound as an oil (12.0 g).