Molybdenum(VI) oxides bearing 1,4,7-triazacyclononane and 1,1,1-tris(aminomethyl)ethane ligands: Synthesis and catalytic applications

摘要: Abstract A series of ionic dioxomolybdenum(VI) complexes general formula [MoO 2 Cl(L)]Y containing tridentate nitrogen ligands [L = 1,4,7-triazacyclononane (tacn), 1,1,1-tris(methylaminomethyl)ethane (Me 3 -tame) and N , ′, ″-tribenzyl-1,1,1-tris(methylaminomethyl)ethane (Bn Me -tame); Y = Cl, BF 4 − ] were prepared by replacement the solvent molecules one chloride in adducts MoO Cl (solv) (solv = THF, DMF). The examined as catalysts for epoxidation cyclooctene at 55 °C, using tert -butyl hydroperoxide ( t -BuOOH) oxidant. kinetic profiles initial activities (60–100 mol mol Mo −1  h ) comparable with those usually exhibited L bearing bidentate heterocyclic amines. tricarbonyl -tame)M(CO) (M = Mo, Cr) also used directly catalyst precursors -BuOOH. Induction periods observed due to relatively slow oxidative decarbonylation formation active oxidising species. When complex was used, 1,2-epoxycyclooctane only product, while Cr a significant amount 1,2-cyclooctanediol formed enhanced Lewis acidity catalyst. tame further studied or cyclododecene, 1-octene, trans -2-octene, R )-(+)-limonene α-pinene.