Monooxygenase-like oxidation of hydrocarbons by hydrogen peroxide catalyzed by manganese porphyrins and imidazole: selection of the best catalytic system and nature of the active oxygen species

Sorption and catalysis by robust microporous metalloporphyrin framework solids

“…Typical turnover numbers of 2 to 12 mol product/ mol catalyst are reported for the homogeneous phase hydroxylation of cyclohexane with manganese(III) tetraphenylporphyrins using a variety of oxidants and reaction times [46][47][48][49][50]. The PIZA-5 turnover numbers obtained in the kinetic studies are somewhat better (30 to 40), but on the same order of magnitude, making As indicated, a second dosage of 500 equivalents PhIO was added at 96 h this heterogeneous system comparable.…”

Direct Selective Oxidative Functionalization of C–H Bonds with H2O2: Mn-Aminopyridine Complexes Challenge the Dominance of Non-Heme Fe Catalysts

“…The 3:1 cyclohexanol:cyclohexanone ratio, the high (11.5) 3 • :2 • adamantane oxidation selectivity, the absence of effect of dioxygen on the oxidation outcome, and selective (non-statistical) oxygenation of heptane were indicative of a metal-mediated rather than radical-driven oxidation mechanism [51]. The authors hypothesized that the oxidation could be performed by the Mn V =O intermediate, the role of imidazole consisting in promoting the heterolytic cleavage of the O-O bond, to form the manganese-oxo species [52]. of heptane were indicative of a metal-mediated rather than radical-driven oxidation mechanism [51].…”

“…of heptane were indicative of a metal-mediated rather than radical-driven oxidation mechanism [51]. The authors hypothesized that the oxidation could be performed by the Mn V =O intermediate, the role of imidazole consisting in promoting the heterolytic cleavage of the O-O bond, to form the manganese-oxo species [52]. Banfi with co-workers considered a series of Mn-porphyrin complexes 2-4 as alkane oxidation catalysts and found that the introduction of a nitro group (3 and 4 vs. 2) resulted in an increase of activity and stability of the catalysts, eventually resulting in higher yields of oxygenated products [53].…”

Effect of Temperature and Reaction Time on the Synthesis of Butadiene Monoepoxide Using Iron Complex as an Efficient Catalyst

“…Transition metal compounds such as metalloporphyrin [12], titanosilicates [13], methyltrioxorhenium [14], tungsten compounds [15][16][17][18], polyoxometalates [19,20], and manganese complexes [21] have been employed as a catalyst for H2O2-based epoxidation, either homogeneous or heterogeneous. Unfortunately, these systems have disadvantages, such as low efficiency of H2O2 utilization and low selectivity to epoxides (or low stereospecificity) [12][13][14][15][16][17][18][19][20], limited number of applicable olefins [21], and high reaction temperatures [15][16][17] complexes were reported to efficiently epoxidize aromatic or substituted alkenes with high yields using peroxycarboxylic acids at -80 ℃, where salen is N,N'-bis(salicylidene)ethylenediamine [23,24]. However, these catalysts are not effective in epoxidizing most terminal and trans-olefins [25][26][27][28].…”