In the presence of phosphine catalyst and pinacolborane, ynones undergo 1,2-reduction while ynoates undergo
Synthesis of guanidine-linked NHC can be achieved easily and its copper complexes were isolated and fully characterized. These Cu complexes are found to be versatile catalysts for hydroboration, semihydrogenation and carboboration of alkynes in a highly stereo- and regioselective fashion.