Excited-state protonation and reduction enables the umpolung Birch reduction of naphthalenes

Chem, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 1, 2024

Язык: Английский

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Atmosphere Effects on Arene Reduction with Lithium and Ethylenediamine in THF

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 3, 2025

Birch reductions employing lithium metal have been performed mostly under argon due to concerns about forming nitrides from the reduction of dinitrogen if nitrogen. Although it is generally understood that inert atmospheres are standard for and Birch-type (lithium, ethylenediamine, t-BuOH, THF) reductions, atmosphere effect on has not studied. Herein, we report model substrates using ethylenediamine in THF various atmospheric conditions. The nitrogen afforded essentially same yields. Surprisingly, oxygen only perturbed yields some cases but also controlled regioselectivity a subset naphthalenes. We propose mechanism underlying unexpected oxygen-dependent This work shows may be account fraction oxygen-sensitive reductions.

Язык: Английский

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Enzymatic Birch reduction via hydrogen atom transfer at [4Fe-4S]-OH2 and [8Fe-9S] clusters

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Апрель 4, 2025

Abstract The alkali metal- and ammonia-dependent Birch reduction is the classical synthetic method for achieving dihydro additions to arenes, typically yielding 1,4-cyclodienes. A mild biological alternative this process are 1,5-dienoyl-coenzyme (CoA)-forming class I II benzoyl-CoA reductases (BCRs), widely abundant key enzymes in biodegradation of aromatic compounds at anoxic environments. To obtain a comprehensive mechanistic understanding BCR catalysis, we produced active site subunits from denitrifying bacterium determined X-ray structure its substrate product complexes 1.4 Å revealing non-canonical double-cubane [8Fe-9S] aqua-[4Fe-4S] clusters. Together with kinetic, spectroscopic QM/MM studies, provide evidence radical mechanism [4Fe-4S] cluster-bound water molecule acting as hydrogen atom electron donor potentials beyond redox window. An analogous Birch-like applied by BCRs catalytic bound tungsten- bis -metallopterin cofactor. use activated, metal-bound ligands serves basic blueprint future enzymatic or biomimetic processes.

Язык: Английский

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Birch reductive arylation by mechanochemical anionic activation of polycyclic aromatic compounds

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Май 30, 2025

Birch reduction is a well-known process for transforming aromatic compounds. The of rings using alkali metals produces anionic species that react with protons or electrophiles. Generally, this reaction accompanied by significant limitations in the available nucleophiles, since most cases only alkyl halides and silyl chlorides are available. In particular, arylation unfunctionalized polycyclic hydrocarbons (PAHs), so-called reductive arylation, has not yet been investigated. Herein, we report mechanochemical activation lithium(0) wire, followed addition various fluoroarenes. Specifically, products but also formal C-H can be obtained from PAHs, achieving one-pot annulative π-extension to give nanographenes. This unique rarely achieved solution, shows interesting reactivity lithium metal fluoroarenes solid state.

Язык: Английский

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Mechanochemical Synthesis of Iron Aluminyl Complexes

Dalton Transactions, Год журнала: 2024, Номер 53(30), С. 12450 - 12454

Опубликована: Янв. 1, 2024

A series of molecular iron aluminyl complexes with unsupported Al–Fe bonds have been prepared in the solid state by mechanochemical synthesis.

Язык: Английский

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Calcium Carbide (CaC₂) as a C₂‐Synthon by Mechanochemistry

ChemPlusChem, Год журнала: 2024, Номер unknown

Опубликована: Май 31, 2024

Abstract Mechanochemical reactions by ball milling have opened new avenues in chemical synthesis. Particularly, mechanochemistry has facilitated the reaction of insoluble materials to simplify stablished synthetic protocols and develop ones. One notable application involves use calcium carbide (CaC 2 ) as a C ‐synthon through mechanochemistry, which offered more practical alternative incorporate ‐units compared conventional highly flammable gaseous acetylene. For example, milling, acetylenic anions [C ] 2− found CaC been harnessed for synthesis diverse functional carbon well discrete organic molecules. This Concept aims contribute conceptualization this innovative approach while highlighting both its advantages challenges inherent .

Язык: Английский

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Mechanochemical Synthesis of a Sodium Anion Complex [Na⁺(2,2,2-cryptand)Na^–] and Studies of Its Reactivity: Two-Electron and One-Electron Reductions

Inorganic Chemistry, Год журнала: 2024, Номер 63(32), С. 15247 - 15258

Опубликована: Июль 29, 2024

Group 1 metal molecular chemistry is dominated by a +1 oxidation state, while 0 state widespread in the metals. A more exotic, yet still available, of group -1, i.e., alkalide. Reported as early 1970s, alkalides appear every modern inorganic textbook an iconic chemical curiosity, their reactivity remains unexplored. This due to synthetic hurdles. In this work, we report first facile synthesis archetypical alkalide complex, [Na

Язык: Английский

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Mechanochemical Deprotection of t-Butoxycarbonyl (Boc) Group Using Basic Alumina

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(38), С. 7811 - 7816

Опубликована: Янв. 1, 2024

A solvent-free, operationally simple, and chemoselective mechanochemical method for

Язык: Английский

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Green Chemistry Tools in Mechanochemistry

Elsevier eBooks, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

Язык: Английский

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