Interactional Features of (RO)4Ti Species and Their Zr and Hf Analogues

: Tetroxides of Group 4 elements are benchmark catalysts for aldol reactions and oxidation processes, achieving high yields and regio-, diastereo-, and enantioselectivities. Our computational analyses and experimental studies, performed in solution and solid, consistently reveal that these tetroxides form attractive interactions with lone pair compounds exhibiting distinctive σ-hole bond features. We propose naming these novel bondings as titan bonds (TnBs). These new insights into Ti/Zr/Hf tetroxide interactions may significantly aid in designing more effective catalysts with enhanced selectivities.