Synthesis and catalytic applications of palladium(II) complexes supported by hydroxyl?functionalized triazolylidenes

A series of allyl ( 1?3 ) and cinnamyl ( 4?6 ) palladium(II) complexes supported by hydroxyl functionalized triazolylidenes have been prepared. All new compounds were fully characterized by means of 1 H and 13 C NMR spectroscopy, FT?IR and elemental analyses. The new triazolylidene palladium complexes were tested as precatalysts in the coupling of aryl chlorides with boronic acids and the coupling of esters with amines to produce biphenyls and amides, respectively. According to the overall results, complexes 4 and 5 displayed the highest catalytic activity in both coupling processes, providing good to excellent yields under mild reaction conditions and using a wide range of substrates.