Synthesis, Crystal Structure, and Catalytic Properties of Novel Dioxidomolybdenum(VI) Complexes with Tridentate Schiff Base Ligands in the Biomimetic and Highly Selective Oxygenation of Alkenes and Sulfides

Four novel dioxidomolybdenum(VI) complexes [MoO 2 (L x )(CH 3 OH)] have been synthesized, using 2[( E )‐(2‐hydroxy‐2‐phenylethylimino)methyl]phenol derivatives as tridentate ONO donor Schiff base ligands (H 2 L x ) and MoO 2 (acac) 2 . A monoclinic space group was determined by X‐ray crystallography from single‐crystal data of a sample of these new complexes. The epoxidation of alkenes by using tert ‐butyl hydroperoxide and oxidation of sulfides to sulfoxides by urea hydrogen peroxide were efficiently enhanced with excellent selectivity under the catalytic influence these new Mo VI complexes. The high efficiency and relative stability of the catalysts have been observed by turnover numbers and UV/Vis investigations. The electron‐poor and bulky ligands promoted the effectiveness of the catalysts.