1, 2-Dihalogenation and oxy-1, 1-dihalogenation of alkynes by N-halosuccinimides can be selectively realized through using different reaction conditions. α, β-Dihalo alkenes were obtained exclusively using THF as solvent without using any catalyst, while α, α-dihalo ketones were synthesized using a mixed solvent of THF and H2O in the presence of FeCl3· 6H2O. Terminal aromatic alkynes are smoothly transformed into α, α-dihalo ketones on ...