Aminopyridine Iron and Manganese Complexes as Molecular Catalysts for Challenging Oxidative Transformations

Codolà, Zoel; Lloret‐Fillol, Julio; Costas, Miguel

doi:10.1002/9781118869994.ch07

Cited by 19 publications

(18 citation statements)

References 223 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[77] On the other hand, for the active species of cytochrome P450 enzymes and other selectiveh emec atalysts,t he adamantane regioselectivity can achieve valuesa sh igh as 48. [42,68] Thus,w hile lowv alueso ft he tertiary to secondary ratio (38 8/28 8 < 6) are indicative of af ree-radical mechanism, 38 8/28 8 ratios higher than 13-15 strongly point to am etal-based mechanism.…”

Section: Regioselectivitymentioning

confidence: 93%

“…[39,42,51,52] Thes electivem etal-based oxidative pathwayoften competes with arather unselective radical chain autoxidation process initiated by oxygencentered radicals produced in Fenton-typer eactions between ironi onsa nd peroxides [53] (Scheme 1). Such autoxidation processes suffera ll the intrinsic limitations on selectivity and, above all, predictability always associated with highly energetic radical processes.C ompetition between the metal-based and the free-radical oxidation processes is dependent on reaction conditions,c atalyst structurea nd oxidant employed.…”

Section: Introductionmentioning

confidence: 99%

“…[11][12][13][14][15][16][17][18][19][20][21][22][23] These complexes proved to be also excellent catalysts for epoxidation [24][25][26][27][28][29][30][31] or cis-dihydroxylation [32][33][34][35][36][37][38] of olefins. Such catalysts offer several advantagesw hen compared to the currently used catalytic systems:( i) the abundant, cheap and environmentally friendly iron and H 2 O 2 are used as the metal centera nd the terminal oxidant, respectively,( ii)aselective, metal-based oxidation mechanism devoid of free diffusing radical formation is mostly operating, [13,[39][40][41][42] which ensures ag ood degree of selectivity by manipulation of the catalyst structure, [14,17,43] (iii)i nm any cases,s ynthesis of non-heme amine-based iron complexes is significantly less demanding than that of metalloporphyrin heme model complexes. [44][45][46][47] Thed evelopment of non-hemea mine-based iron catalysts has been accompanied over the years by ap arallels tudy of non-heme imine-based ironc ounterparts,a lthough the latter received less interest probably due to the conviction that imines (or Schiff bases) are not robust enough to be conveniently employed in typical oxidation conditions.Y et, some imin...…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Non‐Heme Imine‐Based Iron Complexes as Catalysts for Oxidative Processes

2016

View full text Add to dashboard Cite

Non-heme iron complexes are emerging as powerful and versatile catalysts in several oxidative transformations. Them ost investigated iron complex structures are based on aminopyridine ligands,b ut an umber of imine-based ligands have been also tested. In this review ac ollection of recent results obtained in oxidation catalysisw ith non-heme iminebased iron complexes is presented. Theirc atalytic performances in C À H, C=Ca nd À S À oxidation are spread over aw ide range of efficiency,g oing from very low to quite high.S uch performances are discussed, whenever possible,i nl ight of the operating reactionm echanismsa nd of catalyst stability.I n order to facilitate the discussion,a ni nitial survey of the most useful mechanistic tools widelya pplied to distinguish am etal-based oxidation from ar adicalchain process is also reported. Imine-basedc atalysts are divided into twoc lasses:( i) salen-Fec omplexes, and (ii)i mine-Fe complexes.I ns ome cases clues for free-radical oxidation mechanisms have been reported whilei no ther casese vidence for metal-based mechanisms has been collected. Thep referredm echanisticp athway is shown to be af unction of catalyst structure and features

show abstract

Section: Regioselectivitymentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Non‐Heme Imine‐Based Iron Complexes as Catalysts for Oxidative Processes

2016

View full text Add to dashboard Cite

show abstract

“…However, in catalyst systems relying on isostructural Fe catalysts, such evidence was gained by EPR spectroscopy taking advantage of the low-spin (S = 1 / 2 ) structure of known oxoiron(V) intermediates [189]. Costas in recent years has carried out many valuable works on functionalization of carbon-hydrogen bond catalyzed by nonheme complexes with polyamino ligands [190][191][192][193]. Additionally, very important works on complexes with polydentate ligands as catalysts have been reported by Nam and colleagues [194].…”

Section: New Types Of Ligands and Catalystsmentioning

confidence: 99%

New Trends in Oxidative Functionalization of Carbon–Hydrogen Bonds: A Review

Shul’pin

2016

Catalysts

174

View full text Add to dashboard Cite

This review describes new reactions catalyzed by recently discovered types of metal complexes and catalytic systems (catalyst + co-catalyst). Works of recent years (mainly 2010-2016) devoted to the oxygenations of saturated, aromatic hydrocarbons and other carbon-hydrogen compounds are surveyed. Both soluble metal complexes and solid metal compounds catalyze such transformations. Molecular oxygen, hydrogen peroxide, alkyl peroxides, and peroxy acids were used in these reactions as oxidants.

show abstract

“…Various biomimetic systems with dioxygenase reactivity have been investigated, and these have helped to elucidate the biologically relevant catalytic mechanisms. [108][109][110][111][112][113] A wide variety of published work on the stoichiometric and catalytic oxidation of organic molecules with low-molecularweight non-heme iron model complexes is available, [57,114,115] and this includes oxygen-transfer reactions, e.g. sulfoxidation, [91,116] oxidative demethylation, [117] and methane formation [118] as well as the oxidation of alkanes and alkenes, [91] which are of specific interest in the degradation of organic matter in nature.…”

Section: Relevant Oxidation Reactionsmentioning

confidence: 99%

Iron-catalysed oxidation and halogenation of organic matter in nature

et al. 2015

View full text Add to dashboard Cite

Environmental context. Natural organohalogens produced in and released from soils are of utmost importance for ozone depletion in the stratosphere. Formation mechanisms of natural organohalogens are reviewed with particular attention to recent advances in biomimetic chemistry as well as in radical-based Fenton chemistry. Iron-catalysed oxidation in biotic and abiotic systems converts organic matter in nature to organohalogens.Abstract. Natural and anthropogenic organic matter is continuously transformed by abiotic and biotic processes in the biosphere. These reactions include partial and complete oxidation (mineralisation) or reduction of organic matter, depending on the redox milieu. Products of these transformations are, among others, volatile substances with atmospheric relevance, e.g. CO 2 , alkanes and organohalogens. Natural organohalogens, produced in and released from soils and salt surfaces, are of utmost importance for stratospheric (e.g. CH 3 Cl, CH 3 Br for ozone depletion) and tropospheric (e.g. Br 2 , BrCl, Cl 2 , HOCl, HOBr, ClNO 2 , BrNO 2 and BrONO 2 for the bromine explosion in polar, marine and continental boundary layers, and I 2 , CH 3 I, CH 2 I 2 for reactive iodine chemistry, leading to new particle formation) chemistry, and pose a hazard to terrestrial ecosystems (e.g. halogenated carbonic acids such as trichloroacetic acid). Mechanisms for the formation of volatile hydrocarbons and oxygenated as well as halogenated derivatives are reviewed with particular attention paid to recent advances in the field of mechanistic studies of relevant enzymes and biomimetic chemistry as well as radical-based processes.

show abstract

Aminopyridine Iron and Manganese Complexes as Molecular Catalysts for Challenging Oxidative Transformations

Cited by 19 publications

References 223 publications

Non‐Heme Imine‐Based Iron Complexes as Catalysts for Oxidative Processes

Non‐Heme Imine‐Based Iron Complexes as Catalysts for Oxidative Processes

New Trends in Oxidative Functionalization of Carbon–Hydrogen Bonds: A Review

Iron-catalysed oxidation and halogenation of organic matter in nature

Contact Info

Product

Resources

About