The highly efficient click reaction between terminal alkynes and azides has been achieved on water using 5 ruthenium complex RuH 2 (CO)(PPh 3 ) 3 as the catalyst, and the catalyst loading was decreased to 0.2 mol% on water from 5 mol% in organic solvent. The RuH 2 (CO)(PPh 3 ) 3 /H 2 O system also catalyzed the one-pot click reaction of bromides, sodium azide and alkynes; in this process, azides formed in situ and then underwent a click reaction with alkynes. In both aqueous processes, 1,4-disubstituted 1,2,3-triazoles were obtained in 71-89% yield with high regioselectivity.

A copper(ii) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone provides a novel, concise method for constructing isochromeno[3,4-b]chromene in 35-94% yields. The tandem reaction involves cycloisomerization, formal [4+2] cycloaddition and an elimination process.

A tandem reaction of benzyne with functionalized benzylidenephthalan for the synthesis of a variety of phenanthro[10,1-bc]furans has been achieved for the first time in moderate to good yields. The reaction mechanism involves a Diels–Alder reaction and an intermolecular nucleophilic addition reaction as the key steps.

The ruthenium hydride complex RuH(2)(CO)(PPh(3))(3) was found to be an effective catalyst for the cycloaddition reactions of terminal alkynes and azides. In the presence of RuH(2)(CO)(PPh(3))(3), various azides reacted with a range of terminal alkynes to produce 1,4-disubstituted 1,2,3-triazoles with 100% selectivity and moderate to excellent yields.