The π-type and O-activated hetero-and homo-atomic catalytic systems were thoroughly assessed and compared from a mechanistic perspective. The analysis focused on understanding the underlying mechanisms of these two activation modes and their respective impact on the catalytic processes. The O-and π-type activation modes of the heteroatomic catalysts (CAT3, CAT4, CAT6, and CAT8) different substrate activation modes but consistently shared the same anticipated 53 mechanism for TS1 (Figure ). Notably, the π-type activated TS1 was found to be more energetically stable in all the bidentate catalytic systems, while the monodentate CAT4 showed a preference for the O-activation mode. The likely reason for this observation lies in the ability of the bidentate catalysts to simultaneously activate both sites of the trans-crotonophenone substrate, the carbonyl oxygen and the α-carbon. In contrast, the monodentate CAT4 lacks this feature and is limited to interactions solely with either the carbonyl oxygen in the O-activation mode or the α-carbon in the π-type activation mode. , for a comprehensive free energy profile).