Dioxomolybdenum(VI) compounds with α-amino acid donor ligands as catalytic precursors for the selective oxyfunctionalization of olefins

• Published in: Molecular catalysis Vol. 446; pp. 39 - 48
• Main Authors: Abdalghani, Issam, Biancalana, Lorenzo, Aschi, Massimiliano, Pampaloni, Guido, Marchetti, Fabio, Crucianelli, Marcello
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2018
• Subjects: cis-Dioxomolybdenum; Heterogeneous catalysis; Olefin oxidation; tert-Butyl hydroperoxide; α-Amino acid; α-Amino acid; Heterogeneous catalysis; cis-Dioxomolybdenum; Olefin oxidation; tert-Butyl hydroperoxide
• ISSN: 2468-8231; 2468-8231
• DOI: 10.1016/j.mcat.2017.12.018

[Display omitted] •Five dioxomolybdenum α-amino acid containing compounds were investigated as catalyst precursors for the oxyfunctionalization of olefins.•All the complexes behaved as active catalysts, showing satisfying substrates conversion and high selectivity toward epoxide.•This study confirms the remarkable catalytic potential of heterogeneous cis-dioxo-Mo(VI) systems for green and sustainable processes. A series of cis-dioxomolybdenum(VI) α-amino acid containing compounds I–V has been investigated as potential catalyst precursors for the mild and selective oxyfunctionalization of conjugated or unconjugated olefins like styrene, α-methylstyrene, cis-β-methylstyrene, cyclohexene and cyclooctene, using tert-butyl hydroperoxide (TBHP) as main oxidant. All the I–V complexes behaved as active heterogeneous and recyclable catalysts, showing good to quantitative conversion values of the substrate. In all cases, high selectivity toward the corresponding epoxide formation was detected. No substantial difference in terms of efficiency has been observed among the different catalysts I–V, thus confirming that the different nature of the amino acidic side-chain does not strictly affect the catalytic process. Insights into mechanistic details and reaction free energy profile of catalytic oxidations by means of quantum chemical calculations have been discussed.