The synthesis of four novel, tridentate aminophenolate ligands HL1-HL4, bearing amide functionalities is reported. Reaction of these ligands with a dioxido molybdenum(VI) precursor led, depending on the choice of solvent, to mononuclear complexes of the type [MoO₂L(OMe)] (2, 4, 6) or dinuclear complexes [{MoO₂L}₂(μ-O)] (1, 3, 5, 7), containing one facially, tridentate ONO-ligand per metal center. This synthetic discrimination between dinuclear and mononuclear complexes allows for a comparison between structures and reactivity. Complexes 1-7 were found to be highly active catalysts in the epoxidation of several internal and terminal alkenes. With tert-butyl hydroperoxide (TBHP) as oxidant, precatalyst loadings of 0.0005 mol% (5 ppm) could be realized leading to turnover numbers of up to 110000. The precatalysts also allowed for the use of hydrogen peroxide (0.1 mol% precatalyst) as oxidant as well as various alcohols as “green” solvents, such as ethanol or even tert-butanol (usually an inhibitor of epoxidation).

报道了四个具有酰胺官能团的新颖的三齿氨基酚盐配体HL1 - HL4的合成。这些配体的反应与二氧化钼（VI）的前体主导，这取决于溶剂的选择，单核的类型的配合物[的MoO ₂大号（OME）]（2，4，6）或双核配合物[{的MoO ₂大号} ₂（μ-O）]（1，3，5，7），每个金属中心包含一个面部三齿ONO配体。双核和单核复合物之间的这种合成区分允许在结构和反应性之间进行比较。配合物1 - 7被认为是在多个内部和末端烯烃环氧化高活性催化剂。使用氢过氧化叔丁基（TBHP）作为氧化剂，可以实现0.0005 mol％（5 ppm）的预催化剂载量，从而导致周转数高达110000。该预催化剂还允许使用过氧化氢（0.1 mol％的预催化剂）作为催化剂。氧化剂以及各种醇作为“绿色”溶剂，例如乙醇或什至叔丁醇（通常是环氧化抑制剂）。