{ "id": "ep4vmaw85a", "slug": "metalloradical-catalysis", "title": "Metalloradical catalysis", "updated": "2026-10-15", "topic_path": [ { "id": "physical", "label": "Physical world and mathematics", "api_url": "https://www.edgepedia.org/api/v1/topics/physical" }, { "id": "physical.chemistry", "label": "Chemistry", "api_url": "https://www.edgepedia.org/api/v1/topics/physical.chemistry" }, { "id": "physical.chemistry.methods", "label": "Chemical principles and methods", "api_url": "https://www.edgepedia.org/api/v1/topics/physical.chemistry.methods" }, { "id": "physical.chemistry.methods.chemical-synthesis", "label": "Chemical synthesis", "api_url": "https://www.edgepedia.org/api/v1/topics/physical.chemistry.methods.chemical-synthesis" } ], "geo": [ { "id": "geo.nongeo.t1946.physical.chemistry.methods.chemical-synthesis", "label": "Non-geographic · 1946 to 2000: Chemical synthesis", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.physical.chemistry.methods.chemical-synthesis", "path": [ { "id": "geo.nongeo", "label": "Non-geographic", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo" }, { "id": "geo.nongeo.t1946", "label": "Non-geographic · 1946 to 2000", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946" }, { "id": "geo.nongeo.t1946.physical", "label": "Physical world and mathematics", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.physical" }, { "id": "geo.nongeo.t1946.physical.chemistry", "label": "Chemistry", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.physical.chemistry" }, { "id": "geo.nongeo.t1946.physical.chemistry.methods", "label": "Chemical principles and methods", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.physical.chemistry.methods" }, { "id": "geo.nongeo.t1946.physical.chemistry.methods.chemical-synthesis", "label": "Chemical synthesis", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t1946.physical.chemistry.methods.chemical-synthesis" } ] }, { "id": "geo.nongeo.t2001.physical.chemistry.methods.chemical-synthesis", "label": "Non-geographic · 2001 to 2020: Chemical synthesis", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001.physical.chemistry.methods.chemical-synthesis", "path": [ { "id": "geo.nongeo", "label": "Non-geographic", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo" }, { "id": "geo.nongeo.t2001", "label": "Non-geographic · 2001 to 2020", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001" }, { "id": "geo.nongeo.t2001.physical", "label": "Physical world and mathematics", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001.physical" }, { "id": "geo.nongeo.t2001.physical.chemistry", "label": "Chemistry", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001.physical.chemistry" }, { "id": "geo.nongeo.t2001.physical.chemistry.methods", "label": "Chemical principles and methods", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001.physical.chemistry.methods" }, { "id": "geo.nongeo.t2001.physical.chemistry.methods.chemical-synthesis", "label": "Chemical synthesis", "api_url": "https://www.edgepedia.org/api/v1/geo/geo.nongeo.t2001.physical.chemistry.methods.chemical-synthesis" } ] } ], "excerpt": "Metalloradical catalysis is a catalytic method in organic chemistry in which open-shell transition-metal complexes, chiefly cobalt(II) porphyrins, generate and control radical intermediates to form chemical bonds selectively under neutral conditions.", "snippet": "Metalloradical catalysis is a catalytic method in organic chemistry in which open-shell transition-metal complexes, chiefly cobalt(II) porphyrins, generate and control radical intermediates to form chemical bonds selectively under neutral conditions.", "node": "physical.chemistry.methods.chemical-synthesis", "markdown": "# Metalloradical catalysis\n\nMetalloradical catalysis (MRC) is a catalytic method in organic chemistry in which paramagnetic, open-shell transition-metal complexes generate and control radical intermediates to form chemical bonds in selective transformations of organic molecules. Where classical organometallic catalysis proceeds by two-electron, concerted ionic steps (oxidative addition, migratory insertion, reductive elimination), MRC proceeds by one-electron, stepwise radical elementary steps, and where free-radical chemistry uses initiators, light, or electricity to make uncontrolled radicals, MRC generates metal-entangled radicals without traditional radical initiators, photolysis or electrolysis.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/) The archetypal platform is cobalt(II) porphyrin chemistry.[2](https://doi.org/10.1016/j.chempr.2021.04.004)\n\n| Key fact | Detail |\n|---|---|\n| Catalyst archetype | Co(II) porphyrins, stable 15-electron metalloradicals with low-spin \\( d^{7} \\) configuration[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/) |\n| Oxidation-state pattern | Metal changes by one unit per step (\\( M_{n} \\rightarrow M_{n+1} \\rightarrow M_{n} \\)), not two as in closed-shell catalysis[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/) |\n| Turnover mode | Homolytic radical substitution (\\( S_{\\mathrm{H}}1/S_{\\mathrm{H}}2 \\)), feasible because M–Y bonds (\\( Y = CR_{2}, NR, O \\)) are weaker than C–Y bonds[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/) |\n| Dominant metal | Co(II)-based catalysts account for roughly 90% of the carbene-radical literature[3](https://pubs.acs.org/doi/full/10.1021/acscatal.3c00591) |\n| Flagship asymmetric result | Heteroaryl cyclopropanation: 99% yield, 92% de, 99% ee at room temperature[4](https://par.nsf.gov/servlets/purl/10279582) |\n| Newest platform | Fe(III) porphyrins for asymmetric C–H amination of aryl azides, 92% ee and 97% yield[5](https://pubs.acs.org/doi/10.1021/jacs.5c07473) |\n| Conditions | Neutral, nonoxidative, additive-free; N2 as the only byproduct[6](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/) |\n\n## How it works\n\nA metal-centered radical activates a substrate homolytically. Square-planar Co(II) porphyrins such as \\( [\\mathrm{Co}^{\\mathrm{II}}(\\mathrm{TPP})] \\) are defined open-shell doublets (\\( S = 1/2 \\), spin \\( d^{7} \\)); they activate diazo compounds by intramolecular metal-to-substrate single-electron transfer with N2 extrusion, giving cobalt(III)–carbene radical intermediates, and activate organic azides analogously to α-Co(III)-aminyl radicals.[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC8385710/) These α-metal radicals then abstract hydrogen atoms from C–H substrates (HAA) and the resulting carbon radicals undergo radical substitution (RS) to form C–N or C–C bonds.[8](https://pmc.ncbi.nlm.nih.gov/articles/PMC7726091/)\n\nThe rebound step is orbital-specific: in cyclopropanation, the cobalt(III)-carbene radical adds stepwise to an alkene to give a γ-radical, which attacks the \\( \\sigma^{*} \\)-orbital of the Co–C bond, releasing cyclopropane and regenerating Co(II); C–H insertion analogously proceeds by HAT into the \\( \\pi^{*} \\) Co–C SOMO (singly occupied molecular orbital in radical intermediates) followed by the same rebound.[3](https://pubs.acs.org/doi/full/10.1021/acscatal.3c00591) Computational analysis shows the Co–carbene has a single metal–carbene bond with spin density localized on the carbene carbon (>99% p-character), making it nucleophilic and tunable by α-substituents, unlike electrophilic Fischer carbenes.[9](https://pubmed.ncbi.nlm.nih.gov/21643517/) Intermediates have been detected by EPR (with 13C labeling showing hyperfine coupling to cobalt), identified by HRMS-ESI, trapped with TEMPO, and characterized by [X-ray crystallography](https://www.edgepedia.org/x-ray-crystallography).[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/)\n\n## How it is done\n\nThe dominant platform is Co(II) complexes of \\( D_{2} \\)-symmetric chiral amidoporphyrin ligands (ChenPhyrin, QingPhyrin, ZhuPhyrin, HuPhyrin families), whose amide N–H groups hydrogen-bond to sulfonyl S=O units of the α-Co(III)-aminyl intermediate and whose pocket-like chiral environment combines H-bonding, π-stacking, and van der Waals interactions.[6](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/) Substrate classes are diazo compounds (including donor-substituted, α-formyl, α-alkynyl, and heteroaryl diazo reagents), sulfonyl and alkoxysulfonyl azides, and carbonyl azides.[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/) [Ligand](https://www.edgepedia.org/ligand) structure controls selectivity strongly: replacing methoxy with phenoxy groups raised enantioselectivity in intermolecular amination from 20% to 86% ee,[8](https://pmc.ncbi.nlm.nih.gov/articles/PMC7726091/) and shortening a HuPhyrin alkyl bridge from \\( C_{8} \\) to \\( C_{6} \\) raised it from 49% to 90% ee at unchanged 99% yield.[10](https://doi.org/10.1016/j.chempr.2023.09.010)\n\nAlternative platforms exist. Anionic TAML-ligated Co(III) complexes form nitrene radicals by ligand-to-substrate single-electron transfer and catalyze aziridination, sulfimidation, and \\( \\mathrm{C(sp^{3})} \\)–H amination under ambient conditions tolerant of O2 and H2O.[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC8385710/) Five-coordinate Fe(III) porphyrins (stable 15e \\( d^{5} \\) metalloradicals) extend MRC to aryl azides,[5](https://pubs.acs.org/doi/10.1021/jacs.5c07473) and Ti(III), Cu(I), and Ni(I) systems cover epoxide openings, asymmetric radical cross-couplings, and [C–H functionalization](https://www.edgepedia.org/c-h-functionalization).[1](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/)\n\n## Origin\n\nEarlier radical-metal work the field built on includes Kochi and Krusic's ESR studies of allylic radicals (1968, [Journal of the American Chemical Society](https://www.edgepedia.org/journal-of-the-american-chemical-society)),[11](https://doi.org/10.1021/ja01027a066) and RajanBabu and Nugent's selective generation of free radicals from epoxides using a transition-metal radical (1994, Journal of the American Chemical Society).[12](https://doi.org/10.1021/ja00082a021) An early flagship of the modern program is the cobalt-catalyzed asymmetric cyclopropanation of electron-deficient olefins by Ying Chen, Joshua V. Ruppel and [X. Peter Zhang](https://www.edgepedia.org/x-peter-zhang) (Journal of the American Chemical Society, 2007).[13](https://doi.org/10.1021/ja074613o) The radical mechanism was then established experimentally and computationally: 'carbene radicals' in \\( \\mathrm{Co}^{\\mathrm{II}} \\)(por)-catalyzed cyclopropanation were described by Dzik and colleagues (2010, Journal of the American Chemical Society),[14](https://doi.org/10.1021/ja103768r) cobalt(III)-carbene radicals were isolated as key intermediates by Lu and colleagues (2011, Journal of the American Chemical Society),[15](https://doi.org/10.1021/ja203434c) and porphyrin-Co(III)-'nitrene radical' species were characterized by Goswami and colleagues (2015, Journal of the American Chemical Society).[16](https://doi.org/10.1021/jacs.5b01197) Reviews credit Zhang's group with establishing MRC as a conceptually distinct approach to controlling radical reactivity and stereoselectivity.[2](https://doi.org/10.1016/j.chempr.2021.04.004)\n\n## Variants\n\n**Radical C–H amination** includes intramolecular 1,5-amination of aryl- and alkylsulfonyl azides, which gives chiral cyclic sulfonamides under neutral, nonoxidative conditions.[6](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/) Intermolecular enantioselective amination of α-C–H bonds of esters with fluoroaryl azides was reported as the first catalytic radical system of its kind.[8](https://pmc.ncbi.nlm.nih.gov/articles/PMC7726091/) Convergent allylic [C–H amination](https://www.edgepedia.org/c-h-amination) of isomeric alkene mixtures gives chiral α-tertiary amines with concurrent regio-, diastereo- and enantiocontrol,[17](https://www.nature.com/articles/s41557-022-01119-4) and 1,6-amination of alkoxysulfonyl azides at room temperature amines propargylic, allylic, and benzylic C–H bonds at 1,6- over 1,5-positions.[18](https://pubmed.ncbi.nlm.nih.gov/40263670/)\n\n**Cyclopropanation** variants use donor-substituted diazo reagents generated in situ from sulfonyl hydrazones,[19](https://pmc.ncbi.nlm.nih.gov/articles/PMC5266645/) α-formyldiazoacetates,[20](https://pubs.rsc.org/en/content/articlepdf/2017/sc/c7sc00658f) α-alkynyldiazomethanes,[21](https://pmc.ncbi.nlm.nih.gov/articles/PMC9032462/) and 2-pyridyldiazomethane for heteroaryl cyclopropanes.[4](https://par.nsf.gov/servlets/purl/10279582) Other families include stereoselective [C–H alkylation](https://www.edgepedia.org/c-h-alkylation) with acceptor/acceptor diazo reagents (α-methoxycarbonyl-α-diazosulfones),[22](https://pubs.rsc.org/en/content/articlepdf/2015/sc/c4sc02610a) enantioselective radical N-heterobicyclization of N-allylsulfamoyl azides to [3.1.0]-bicyclic sulfamoyl aziridines with HuPhyrin catalysts,[10](https://doi.org/10.1016/j.chempr.2023.09.010) and radical transannulation of 2-(diazomethyl)pyridines.[23](https://doi.org/10.1002/anie.201711209)\n\n## Applications\n\nThe transannulation chemistry enabled a short total synthesis of (±)-monomorine.[23](https://doi.org/10.1002/anie.201711209) The heteroaryl cyclopropanation platform covers acrylates, acrylamides, acrylonitriles, 1,1-disubstituted and internal olefins such as indene, and was used for late-stage derivatization of estrone.[4](https://par.nsf.gov/servlets/purl/10279582) Representative performance figures: intermolecular amination, 85% yield and 86% ee;[8](https://pmc.ncbi.nlm.nih.gov/articles/PMC7726091/) benzosultam formation, 94% yield and 90% ee, demonstrated on multigram scale;[6](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/) C–H alkylation, 92% yield with 92% de and 92% ee at only 2 mol% catalyst loading at room temperature;[22](https://pubs.rsc.org/en/content/articlepdf/2015/sc/c4sc02610a) α-formyl cyclopropanation, 78% yield, 95:5 dr, and 96% ee at 40 °C.[20](https://pubs.rsc.org/en/content/articlepdf/2017/sc/c7sc00658f) Mechanistic probes support the radical pathway: with 5 equiv TEMPO the cyclic sulfonamide was still the major product (72% yield), and a (Z)-allylic azide gave exclusively the (E)-product in 86% yield with 82% ee, a rare diastereoconvergent amination.[6](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/)\n\n## Limitations and alternatives\n\n**Metal- and substrate-class scope is a hard limit.** Co(II)-based metalloradical catalysts failed to activate aryl azides for intramolecular C–H amination; on the same model substrate, [Co(P1)] gave only trace product while [Fe(P1)Cl] gave 42% yield, and [Co(P2)] failed while [Fe(P2)Cl] gave 99% yield, which motivated the Fe(III) platform.[5](https://pubs.acs.org/doi/10.1021/jacs.5c07473) **Catalyst synthesis is burdensome**: reaching high selectivity required iterative ligand changes, for example replacing tert-butyl with isopropyl esters raised yield from 10% to 99%, and a ligand series moved enantioselectivity from 6% to 92% ee.[5](https://pubs.acs.org/doi/10.1021/jacs.5c07473) Controlling chemo-, regio-, diastereo- and enantioselectivity of highly reactive radicals remains the field-level challenge the method addresses.[17](https://www.nature.com/articles/s41557-022-01119-4)\n\nFor the same \\( \\mathrm{C(sp^{3})} \\)–H transformations, competing platforms perform differently. A 2024 review frames metallaphotoredox catalysis, in which photocatalysis generates the carbon radical and the metal catalyst transforms it, as the most efficient platform for \\( \\mathrm{sp}^{3} \\) C–H functionalization.[24](https://www.nature.com/articles/s41929-024-01215-3) Other radical-generation routes include polarity-matched HAT in triple photoredox/Ni/HAT catalysis, halogen-rad-mediated arylations (bromine atom, 56%–86% yield; chlorine radical, 66%–78% yield), and TBADT/Ni dual catalysis of strong C–H bonds (61%–71% yield, with 5 equiv substrate).[25](https://pmc.ncbi.nlm.nih.gov/articles/PMC12232520/) Copper metallaphotoredox deoxygenative amination of alcohols handles 18 classes of N-nucleophiles with regioisomeric ratios >20:1.[26](https://macmillan.princeton.edu/wp-content/uploads/carson-et-al-2024-free-radical-deoxygenative-amination-of-alcohols-via-copper-metallaphotoredox-catalysis.pdf) Within MRC's own territory, the prior Cu/bisoxazoline C–H alkylation gave only 30–68% yields and was completely inhibited by a para-\\( \\mathrm{NO_{2}} \\) group on a benzylic substrate,[22](https://pubs.rsc.org/en/content/articlepdf/2015/sc/c4sc02610a) and for α-formyldiazoacetates [Rh2(OAc)4] was incompatible while [Co(TPP)] gave under 10%, showing that both Rh carbenoid and simple Co(II) porphyrin catalysis fail where amidoporphyrin MRC succeeds.[20](https://pubs.rsc.org/en/content/articlepdf/2017/sc/c7sc00658f)\n\n## References\n\n1. [Metalloradical Catalysis: General Approach for Controlling Reactivity and Selectivity of Homolytic Radical Reactions (Lee & Zhang, Angew. Chem. Int. Ed. 2024, 63, e202320243)](https://pmc.ncbi.nlm.nih.gov/articles/PMC11097140/)\n2. [Metalloradical catalysis: A radically different approach for molecular construction (Chem, 2021)](https://doi.org/10.1016/j.chempr.2021.04.004)\n3. [Carbene Radicals in Transition-Metal-Catalyzed Reactions (Epping et al., ACS Catalysis perspective, 2023)](https://pubs.acs.org/doi/full/10.1021/acscatal.3c00591)\n4. [Asymmetric Radical Process for General Synthesis of Chiral Heteroaryl Cyclopropanes (NSF public access repository)](https://par.nsf.gov/servlets/purl/10279582)\n5. [Asymmetric C–H Amination via Fe(III)-Metalloradical Catalysis Featuring α-Fe(IV)-Aminyl Radicals as Key Intermediates (JACS, 2025)](https://pubs.acs.org/doi/10.1021/jacs.5c07473)\n6. [Enantioselective Radical Construction of 5-Membered Cyclic Sulfonamides by Metalloradical C–H Amination (JACS 2019)](https://pmc.ncbi.nlm.nih.gov/articles/PMC6854306/)\n7. [Controlling Radical-Type Single-Electron Elementary Steps in Catalysis with Redox-Active Ligands and Substrates (JACS Au perspective, de Bruin group)](https://pmc.ncbi.nlm.nih.gov/articles/PMC8385710/)\n8. [Enantioselective Intermolecular Radical C–H Amination (Jin, Xu, Xie & Zhang, JACS 2020)](https://pmc.ncbi.nlm.nih.gov/articles/PMC7726091/)\n9. [Characterization of Tunable Radical Metal-Carbenes: Key Intermediates in Catalytic Cyclopropanation (Belof et al., Organometallics 2011; PubMed record)](https://pubmed.ncbi.nlm.nih.gov/21643517/)\n10. [New mode of asymmetric induction for enantioselective radical N-heterobicyclization via kinetically stable chiral radical center (Chem, 2024)](https://doi.org/10.1016/j.chempr.2023.09.010)\n11. [Jay K. Kochi, Paul J. Krusic (1968). Isomerization and electron spin resonance of allylic radicals. Journal of the American Chemical Society.](https://doi.org/10.1021/ja01027a066)\n12. [T. V. RajanBabu, William A. Nugent (1994). Selective Generation of Free Radicals from Epoxides Using a Transition-Metal Radical. A Powerful New Tool for Organic Synthesis. Journal of the American Chemical Society.](https://doi.org/10.1021/ja00082a021)\n13. [Ying Chen, Joshua V. Ruppel, X. Peter Zhang (2007). Cobalt-Catalyzed Asymmetric Cyclopropanation of Electron-Deficient Olefins. Journal of the American Chemical Society.](https://doi.org/10.1021/ja074613o)\n14. [Wojciech I. Dzik and colleagues (2010). ‘Carbene Radicals’ in CoII(por)-Catalyzed Olefin Cyclopropanation. Journal of the American Chemical Society.](https://doi.org/10.1021/ja103768r)\n15. [Hongjian Lu and colleagues (2011). Experimental Evidence for Cobalt(III)-Carbene Radicals: Key Intermediates in Cobalt(II)-Based Metalloradical Cyclopropanation. Journal of the American Chemical Society.](https://doi.org/10.1021/ja203434c)\n16. [Monalisa Goswami and colleagues (2015). Characterization of Porphyrin-Co(III)-‘Nitrene Radical’ Species Relevant in Catalytic Nitrene Transfer Reactions. Journal of the American Chemical Society.](https://doi.org/10.1021/jacs.5b01197)\n17. [Metalloradical approach for concurrent control in intermolecular radical allylic C−H amination (Nature Chemistry, 2022)](https://www.nature.com/articles/s41557-022-01119-4)\n18. [Catalytic Metalloradical System for Radical 1,6-C(sp3)-H Amination with Concurrent Control of Site-, Chemo-, and Enantio-selectivity (JACS, 2025; PubMed record)](https://pubmed.ncbi.nlm.nih.gov/40263670/)\n19. [Asymmetric Radical Cyclopropanation of Alkenes with In Situ-Generated Donor-Substituted Diazo Reagents via Co(II)-Based Metalloradical Catalysis](https://pmc.ncbi.nlm.nih.gov/articles/PMC5266645/)\n20. [Metalloradical activation of α-formyldiazoacetates for the catalytic asymmetric radical cyclopropanation of alkenes (Chem. Sci. 2017)](https://pubs.rsc.org/en/content/articlepdf/2017/sc/c7sc00658f)\n21. [Metalloradical Activation of In Situ-Generated α-Alkynyldiazomethanes for Asymmetric Radical Cyclopropanation of Alkenes](https://pmc.ncbi.nlm.nih.gov/articles/PMC9032462/)\n22. [Stereoselective radical C–H alkylation with acceptor/acceptor-substituted diazo reagents via Co(II)-based metalloradical catalysis (Chem. Sci. 2015)](https://pubs.rsc.org/en/content/articlepdf/2015/sc/c4sc02610a)\n23. [Satyajit Roy, Sandip Kumar Das, Buddhadeb Chattopadhyay (2017). Cobalt(II)‐based Metalloradical Activation of 2‐(Diazomethyl)pyridines for Radical Transannulation and Cyclopropanation. Angewandte Chemie International Edition.](https://doi.org/10.1002/anie.201711209)\n24. [Metallaphotoredox catalysis for sp3 C–H functionalizations through single-electron transfer | Nature Catalysis](https://www.nature.com/articles/s41929-024-01215-3)\n25. [Metallaphotoredox: The Merger of Photoredox and Transition Metal Catalysis (Chem Rev)](https://pmc.ncbi.nlm.nih.gov/articles/PMC12232520/)\n26. [Free-Radical Deoxygenative Amination of Alcohols via Copper Metallaphotoredox Catalysis (Carson et al., 2024)](https://macmillan.princeton.edu/wp-content/uploads/carson-et-al-2024-free-radical-deoxygenative-amination-of-alcohols-via-copper-metallaphotoredox-catalysis.pdf)\n\n---\n*Topic: Encyclopedia › Physical world and mathematics › Chemistry › Chemical principles and methods › Chemical synthesis*\n\n*Initially written Sep 29, 2026 · Edited: Oct 15, 2026*\n\n*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*\n\nLicense: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license\n", "same_as": [], "url": "https://www.edgepedia.org/metalloradical-catalysis", "markdown_url": "https://www.edgepedia.org/metalloradical-catalysis.md", "license": { "name": "Edgepedia Community License 1.0", "url": "https://www.edgepedia.org/edgepedia/license", "summary": "Free with credit, commercial use included. AI training is open to everyone. 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Edgepedia Community License 1.0.", "speakable": "Metalloradical catalysis is a catalytic method in organic chemistry in which open-shell transition-metal complexes, chiefly cobalt porphyrins, generate and control radical intermediates to form chemical bonds selectively under neutral conditions." }