“…The late-transition metal pre-catalysts could make thermodynamically processes feasible is through opening a lower activation energy pathway to achieve demanding reaction activity [4]. Many efforts have been devoted to iron and cobalt complex pre-catalysts because of their potential applications [5][6][7][8], in which highly active pre-catalysts are generally demanded. From experimental aspects, it is still relied on massive derivatives of ligands to finely control various factors of metal complex pre-catalysts; moreover, the optimization of catalytic parameters would be required to revaluate the real catalytic scales of complexes synthesized.…”