Mononuclear MnII oxidation catalysts with aminopyridine-based ligands achieve high turnover-number (TON) enantioselective epoxidation of alkenes H2O2. Structure reactivity relations indicate a dependence enantioselectivity and maximum TON on the electronic effect peripheral ligand substituents. Competing H2O2 disproportionation is reduced by carrying out reactions at low temperatures slow addit...

Extensive density functional theory calculations of the O1s binding energies, adsorption energies, and the experimentally measured in situ X-ray photoelectron spectra of oxygen on silver are reported in an effort to clarify which species are present during ethylene epoxidation. We find that the O1s binding energy of an oxygen adatom increases near linearly with its adsorption energy due to the ...

Cooperativity between Brønsted acidic defect sites on oxide surfaces and Lewis acid catalyst sites consisting of grafted calixarene-Ti(IV) complexes is investigated for controlling epoxidation catalysis. Materials are synthesized that, regardless of the surface or calixarene substituent, demonstrate nearly identical UV-visible ligand-to-metal charge-transfer bands and Ti K-edge X-ray absorption...

A chiral iron-sexipyridine complex-hydrogen peroxide mixture is a highly efficient catalytic system for styrene epoxidation with excellent reactivity (3 min, 95% yield) and chemoselectivity (98%).

Some meso-tetra aryl porphyrinato manganese (III) acetate or chloride complexes including meso-tetraphenyl porphyrinato manganese (III) chloride (TPPMnCl), meso-tetrakis(2,3-dimethoxyphenyl)porphyrinato manganese(III) acetate, (T(2,3-OMeP)PMnOAc) and meso-tetrakis(pentaflourophenyl)porphyrinato manganese (III) acetate (TPFPPMnOAc) were synthesized. These porphyrins were used as catalyst in the ...