23355-97-7Relevant articles and documents
Molybdenum(VI) cis-dioxo complexes bearing sugar derived chiral Schiff-base ligands: Synthesis, characterization, and catalytic applications
Zhao, Jin,Zhou, Xiangge,Santos, Ana M.,Herdtweck, Eberhardt,Romao, Carlos C.,Kuehn, Fritz E.
, p. 3736 - 3742 (2003)
Molybdenum(VI)-cis-dioxo complexes bearing sugar derived chiral Schiff-base ligands of general formula MoO2(L)(Solv) have been synthesized (with L = N-salicylidene-D-glucosamine; N-salicylidene-1,3,4,6-tetraacetyl-α-D-glucosamine; N-5-chlorosal
Synthesis of a Fe3O4-CuO@meso-SiO2 nanostructure as a magnetically recyclable and efficient catalyst for styrene epoxidation
Zhang, Xiaowei,Wang, Ge,Yang, Mu,Luan, Yi,Dong, Wenjun,Dang, Rui,Gao, Hongyi,Yu, Jie
, p. 3082 - 3089 (2014)
A novel hybrid Fe3O4-CuO@meso-SiO2 catalyst was successfully fabricated by a multi-step assembly method. CuO nanoparticles were first deposited on the surface of Fe3O4 microspheres to form the Fe
Aerobic Epoxidation of Olefins with Ruthenium Porphyrin Catalysts
Groves, John T.,Quinn, Robert
, p. 5790 - 5792 (1985)
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Chiral ansa-bridged η5-cyclopentadienyl molybdenum complexes: Synthesis, structure and application in asymmetric olefin epoxidation
Zhao, Jin,Herdtweck, Eberhardt,Kühn, Fritz E.
, p. 2199 - 2206 (2006)
Ansa-bridged η5-cyclopentadienyl carbonyl molybdenum complexes were synthesized with stereogenic centers located in the side chain. An exemplary X-ray crystal structure and the catalytic activity for asymmetric olefin epoxidation are reported. In non-chiral epoxidation the compounds show a good catalytic activity, comparable to activities observed for the related non-chiral complexes of composition CpMo(CO)3X (X = Cl, CH3). For the asymmetric epoxidation of trans-β-methylstyrene the chiral induction is up to ca. 20%. The high ring strain of the ansa-bridged system hampers, unfortunately, its stability under oxidative condition.
Polymer-bound chiral (salen)Mn(III) complex as heterogeneous catalyst in rapid and clean enantioselective epoxidation of unfunctionalised olefins
Minutolo, Filippo,Pini, Dario,Salvadori, Piero
, p. 3375 - 3378 (1996)
The application of a new polystyrene-divinylbenzene system containing an optically active (salen)Mn(III) complex in asymmetric epoxidation of unfunctionalised olefins is reported. This system showed a remarkably high reaction speed in the conditions descr
High-yield epoxidations with hydrogen peroxide and tert-butyl hydroperoxide catalyzed by iron(III) porphyrins: Heterolytic cleavage of hydroperoxides
Traylor, Teddy G.,Tsuchiya, Shinji,Byun, Young-Seok,Kim, Cheal
, p. 2775 - 2781 (1993)
The reactions of hydrogen peroxide or tert-butyl hydroperoxide with cyclooctene and norbornene, catalyzed by iron(III) tetrakis(pentafluorophenyl)porphyrin chloride and other electronegatively-substituted porphyrins, produce 60-100% epoxide yields. The ep
Effect of the Ligand Backbone on the Reactivity and Mechanistic Paradigm of Non-Heme Iron(IV)-Oxo during Olefin Epoxidation
Biswas, Jyoti Prasad,Ansari, Mursaleem,Paik, Aniruddha,Sasmal, Sheuli,Paul, Sabarni,Rana, Sujoy,Rajaraman, Gopalan,Maiti, Debabrata
supporting information, p. 14030 - 14039 (2021/05/11)
The oxygen atom transfer (OAT) reactivity of the non-heme [FeIV(2PyN2Q)(O)]2+ (2) containing the sterically bulky quinoline-pyridine pentadentate ligand (2PyN2Q) has been thoroughly studied with different olefins. The ferryl-oxo complex 2 shows excellent OAT reactivity during epoxidations. The steric encumbrance and electronic effect of the ligand influence the mechanistic shuttle between OAT pathway I and isomerization pathway II (during the reaction stereo pure olefins), resulting in a mixture of cis-trans epoxide products. In contrast, the sterically less hindered and electronically different [FeIV(N4Py)(O)]2+ (1) provides only cis-stilbene epoxide. A Hammett study suggests the role of dominant inductive electronic along with minor resonance effect during electron transfer from olefin to 2 in the rate-limiting step. Additionally, a computational study supports the involvement of stepwise pathways during olefin epoxidation. The ferryl bend due to the bulkier ligand incorporation leads to destabilization of both (Formula presented.) and (Formula presented.) orbitals, leading to a very small quintet–triplet gap and enhanced reactivity for 2 compared to 1. Thus, the present study unveils the role of steric and electronic effects of the ligand towards mechanistic modification during olefin epoxidation.
A stand-alone cobalt bis(dicarbollide) photoredox catalyst epoxidates alkenes in water at extremely low catalyst load
Guerrero, Isabel,Romero, Isabel,Teixidor, Francesc,Vi?as, Clara
, p. 10123 - 10131 (2021/12/27)
The cobalt bis(dicarbollide) complex, Na[3,3′-Co(η5-1,2-C2B9H11) (Na[1]), is an effective photoredox catalyst for the oxidation of alkenes to epoxides in water. Advantageous features of Na[1] include its lack of photoluminescence, high solubility and surfactant behavior in aqueous media, as well as the donor ability of the carborane ligand and high oxidizing power of the Co4+/3+ couple. These features differentiate it from the well-known and widely used photosensitizer tris (2,2′-bipyridine) ruthenium(ii) ([Ru(bpy)3]2+), which also participates in electron transfer through an outer sphere mechanism. A comparison of the catalytic performance of [Ru(bpy)3]2+ with Na[1] for alkene photo-oxidation is fully in favor of Na[1], as the former shows very low or null efficiency. With a catalyst loading of 0.1 mol% conversions between 65-97% have been obtained in short reaction times, 15 minutes, with moderate selectivity for the corresponding epoxide, due to the formation of side products as diols. But when the catalyst loading is reduced to 0.01 mol%, the selectivity for the corresponding epoxide increased considerably, being the only compound formed after 15 minutes of reaction (selectivity >99%). High TON values have been obtained (TON = 8500) for the epoxidation of aromatic and aliphatic alkenes in water. We have verified that Na[3,3′-Co(η5-1,2-C2B9H11)2] acts as a photocatalyst in both the epoxidation of alkenes and in their hydroxylation in aqueous medium with a higher rate for epoxidation than for hydroxylation. Preliminary photooxidation tests using methyl oleate as the substrate led to the selective epoxidation of the double bond. These results represent a promising starting point for the development of practical methods for the processing of unsaturated fatty acids, such as the valorisation of animal fat waste using this sustainable photoredox catalyst. This journal is
