Molybdenum(VI) Amino Triphenolate Complexes as Catalysts for Sulfoxidation, Epoxidation and Haloperoxidation

Abstract

Two molybdenum(VI) complexes bearing a C3 symmetrical amino tris-tert-butylphenolate ligand have proved to be air- and water-tolerant catalysts that efficiently catalyse, in high yields and selectivity, the oxidation of sulfides, olefins and halides. In particular high turnover frequencies and turnover numbers (TOF and TON) have been obtained for the cyclooctene epoxidation (catalyst loading down to 0.05%, TONs up to 88,000 and TOFs up to 7500 h−1)

Oxidomolybdenum(VI) complexes with aminoalcohol bis(phenolate) [O,N,O,O′] ligands: Synthesis and catalytic studies

“…In all epoxidation tests, the complete selectivity towards the epoxide was observed according to 1 H NMR spectra. These results are consistent with those reported for comparable molybdenum(VI) amine tris(phenolate) complexes [3]. At room temperature, reasonable differences between the activities of cis and trans isomers were seen (Table 1).…”

“…Applications of such ligands deal mostly with the polymerisation and oxygen transfer reactions catalysed by Lewis acid catalyst. Recently, Licini et al published a study on molybdenum(VI) amine tris(phenolate) complexes which can catalyse a number of oxidations including sulphoxidation, epoxidation and haloperoxidation reactions [3].…”

Oxomolybdenum(VI) complexes with glycine bisphenol [O,N,O,O′] ligand: synthesis and catalytic studies

“…Synthetic approaches to model the active sites of molybdenum enzymes have been either biomimetic (structural modeling) or bioinspired (functional modeling), and rather simple coordination compounds can be studied as models for sophisticated biological systems [2]. For example, the reactions of MoO 2 Cl 2 derivatives with tetrapodal amine trisphenols or aminoalcohol bisphenols are known to lead to neutral mononuclear oxochloromolybdenum(VI) complexes which can catalyze a number of oxidations including sulfoxidation, epoxidation, and haloperoxidation reactions [3,4]. Multidentate phenolic ligands are generally used to make such model compounds.…”

An Efficient Iron Catalyst for the Synthesis of Five‐ and Six‐Membered Organic Carbonates under Mild Conditions

“…[21][22][23] Oxidation catalysis has also been achieved with titanium, vanadium and molybdenum complexes of these ligands. [24][25][26] Whilst similar ironA C H T U N G T R E N N U N G (III) bis(aminophenolate) complexes, widely referred to as ironA C H T U N G T R E N N U N G (III) salan complexes, have previously been investigated for use in many catalytic processes, [21][22][23] ironA C H T U N G T R E N N U N G (III) amine triphenolate complexes have received little or no attention as catalysts. To date, Koch and co-workers have reported the only example of an ironA C H T U N G T R E N N U N G (III) amine triphenolate complex.…”