In the presence of catalytic amount of cesium hydroxide, the nucleophilic addition reaction of selenols to alkyne sulfurnides occurred in tetrahydrofuran at room temperature under nitrogen atmosphere to give highly regio-and stereo-selective (Z)-1-arylthio-2-arylseleno alkenes in 70%～93% yields. The mechanism involved the formation of cesium arylselenides and the nucleophilic addition to the alkynyl sulfides in the presence of cesium hydroxide. The corresponding alkenes were obtained upon hydrolysis.

In the presence of catalytic amounts of cesium chloride, using DMF as solvent, sodium (potassium) carboxylates reacted with α-chloroacetates at room temperature or reacted with alkyl bromides (chlorides) at 60 ℃ to give the corresponding (α-alkoxyformacyl)methyl carboxylic esters and carboxylic esters in ＞90% yields. The catalytic mechanism was discussed.

In the presence of catalytic amount of cesium hydroxide, the hydroselenation of terminal alkynes occurred in N,N-dimethylformamide (DMF) at room temperature under nitrogen atmosphere to afford (E)-1-organseleno-1-alkene in high yields. The reaction mechanism is that selenols reacted with cesium hydroxide to give cesium selenides, which underwent nucleophilic addition to the alkynes to form selenium vinylic anion, hydrolyzed to give product (E)-1-organoselenovinylene and catalyst cesium hydroxide. The method could provide a new and expedient way for the hydroselenation of unactivated alkynes.