A Linear Trinuclear Oxidodiperoxido‐molybdenum(VI) Complex with Single Triazole Bridges: Catalytic Activity in Epoxidation, Alcoholysis, and Acetalization Reactions. Issue 13 (10th April 2018)

• Record Type: Journal Article
• Authors: Antunes, Margarida M.; Amarante, Tatiana R.; Valente, Anabela A.; Almeida Paz, Filipe A.; Gonçalves, Isabel S.; Pillinger, Martyn
• Is Part Of: ChemCatChem. Volume 10:Issue 13(2018)
• Page Start: 2782
• Page End: 2791
• Publication Date: 2018-04-10
• Subjects: alcoholysis -- epoxidation -- molybdenum -- N ligands -- peroxido ligands; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201800232
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: The complex (Htrz)2 [Mo3 O6 (O2 )4 (trz)2 ]⋅ H2 O (1 ), isolated from the reaction of MoO3 with H2 O2 in the presence of 1, 2, 4‐triazole (trz), displays singular structural features such as double bridges comprising one oxido and one triazole ligand, and peripheral oxidodiperoxido‐molybdenum(VI) units. A comparative study was performed regarding the catalytic activity and stability of complex 1 and the hybrid material [MoO3 (trz)0.5 ] (2 ) for the epoxidation of cis ‐cyclooctene (Cy8), the alcoholysis of epoxides, and the acetalization of benzaldehyde (PhCHO). Methanol or ethanol were used as solvents and reagents for the latter two reactions. For the substrates Cy8, styrene oxide, and PhCHO, the corresponding epoxide, β‐alkoxy alcohol, and dialkyl acetal were obtained with 100 % selectivity at very high conversions. In general, 1 performed better than 2 for the different catalytic reactions. Under certain oxidant/co‐solvent conditions used for Cy8 epoxidation, 1 was converted to 2 during the reaction. Abstract : A structurally unparalleled molybdenum(VI) complex has been isolated from the reaction of MoO3 with H2 O2 in the presence of 1, 2, 4‐triazole. The complex leads to selective conversions in catalytic olefin epoxidation, mild acid‐catalyzed ring‐opening of epoxides, and acetalization of benzaldehyde by using alcohols as solvents and nucleophiles.