A Linear Trinuclear Oxidodiperoxido‐molybdenum(VI) Complex with Single Triazole Bridges: Catalytic Activity in Epoxidation, Alcoholysis, and Acetalization Reactions

Abstract

The complex (Htrz)2[Mo3O6(O2)4(trz)2]⋅H2O (1), isolated from the reaction of MoO3 with H2O2 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.

4,6‐Diacetyl Resorcinol Based Vanadium(V) Complexes: Reactivity and Catalytic Applications

“…Overall our results also compare well with the ones obtained with a few Mo‐catalysts which have shown the following values: [MoO 2 Cl 2 ( N , N ‐dimethylbenzamide) 2 ] (99/100 % conversion at 6 h/24 h of reaction time), [MoO 2 {1,4‐bis(2‐hydroxybenzyl)‐( S , S )‐2,2′‐bipyrrolidine}](95 %, 1 h), [MoO 2 Cl 2 (pbim)] (82/98 %, 6 h/24 h), [Mo 2 O 6 {( S )‐4‐(1‐phenylpropyl)‐1,2,4‐triazole} 2 ] (98/100 %, 6 h/24 h), [Mo 2 O 6 (4,4′‐di‐ tert ‐butyl‐2,2′‐bipyridine) 2 ] (93/100 %, 6 h/24 h), (Htrz) 2 [Mo 3 O 6 (O 2 ) 4 (trz) 2 ] · H 2 O (trz = 1,2,4‐triazole)(92/99 %, 6 h/24 h), [{Mo VI O 2 (H 2 O)} 3 ptk(inh) 3 ] (99/100 % 2 h/24 h), and [Mo 2 O 6 (HpypzA)] n (57/82 %, 6/24 h) …”

Recent Progress in Application of Molybdenum-Based Catalysts for Epoxidation of Alkenes

“…Bagherzadeh et al [26] fabricated oligomer molybdenum complexes [MoO 2 (L)] n via the reaction of MoO 2 (acac) 2 and an ONO-type Schiff-base ligand (L = 4-bromo-2-((2-hydroxy-5-methylphenylimino)methyl)phenol) and applied it as a catalyst in alkene epoxidation with high activity and selectivity as well as excellent turnover numbers. Antunes et al [27] designed and prepared the complex (Htrz) 2 [Mo 3 O 6 (O 2 ) 4 (trz) 2 ]•H 2 O, which isolated from the reaction of MoO 3 and H 2 O 2 with the usage of 1,2,4-triazole(trz) and was employed in a model epoxidation reaction with cis-cyclooctene. In order to improve the reactivity of catalysts, Reich's group [28] attached fluorinated moieties to molybdenum tricarbonyl complexes by enhancing Lewis activity through a more electron deficient Mo atom.…”

Synthesis and biological evaluation of heterocyclic 1,2,4-Triazole scaffolds as promising pharmacological agents

“…The presence of aromatic ring in compounds T 1 -T 20 was indicated by the appearance of peak in the range of 1796-1719 cm -1 . DMSO was used as solvent for the analysis of compounds by 1 Tables Table 1 Physicochemical characterization of synthesized derivatives (T 1 -T Table 6 Anticancer screening results of the synthesized compounds (T 1 -T 20 )…”

“…Triazole is an N-bridged aromatic heterocyclic compound that received a considerable attention in recent years due to their biological activities [1]. The name "triazole" was rst use by Bladin in 1855 for describing the carbon-nitrogen ring system C 2 H 3 N 3 [2].…”