Abstract Reaction of alkynyl(p-phenylene)bisiodonium ditriflates with potassium thiocyanate in DMF gave alkynyl thiocyanates and p-iodophenyl(phenyl)iodonium triflate. The latter was readily removed by washing with water. The exclusive sulfur attack of thiocyanate ion suggests that the alkynyl group behaves as a soft acceptor of nucleophiles. The reactions with the enolate anion of 2-phenyl-1,3-indandione in DMF afforded 2-(1-cyclopentenyl)-2-phenyl-1,3-indandiones in the cases of 1-hexynyl- and 1-octynyl-(p-phenylene)bisiodonium ditriflates. In the reactions of 3,3-dimethyl-1-butynyl-, phenylethynyl-, and trimethylsilylethynyl-(p-phenylene)bisiodonium ditriflates, 2-alkynyl-2-phenyl-1,3-indandiones were obtained. The same reactions with the enolate anion of 2-phenyl-1,3-indandione in a mixed solvent of 2-methyl-2-propanol and THF improved the yields of the 1-cyclopentenyl- and alkynyl-substituted indandiones. A large difference in the reaction pathways between the (p-phenylene)bisiodonio and phenyliodonio moieties was observed in the sterically hindered 3,3-dimethyl-1-butynyl systems.