Ionic Schiff base dioxidomolybdenum(VI) complexes as catalysts in ionic liquid media for cyclooctene epoxidation

The preparation of several new molybdenum(VI) complexes containing Schiff base ligands tagged with sulfonate functionalities is presented. The title compounds have been characterized by standard analytical methods including NMR, IR, and mass spectroscopy. X-ray structures of the N-salicylidene-2-aminophenolate dioxidomolybdenum complexes bearing sulfonato groups on the salicylidene moiety (as the sodium and ammonium salts) are described herein accompanied by the structural characterization of the N-salicylidene-2-aminoethanolate sulfonate Schiff base ligand. The activity of the ionic catalysts for cyclooctene epoxidation is shown in different room temperature ionic liquids (i.e. [BMIM][NTf2] (NTf2-=(CF3SO2)2N-), [BMIM][CF3SO3], [EMIM][CH3C6H4SO3]).

Dioxidomolybdenum(VI) complexes derived from sulfonato iminophenolate Schiff base ligands have been synthesized and engaged in cyclooctene epoxidation with t-butyl-hydroperoxide as oxidant in water and ionic liquid media. The best result was obtained with the sulfonato N-salicylidene-2-aminophenolate dioxidomolybdenum complex in the ionic liquid [BMIM][N(CF3SO2)2].Figure optionsDownload as PowerPoint slide