Artificial photosynthesis directed toward organic synthesis

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 27, 2025

In nature, plants convert solar energy into chemical via water oxidation. Inspired by natural photosynthesis, artificial photosynthesis has been gaining increasing interest in the field of sustainability/green science and technology as a non-natural thermodynamically endergonic (ΔG° > 0, uphill) solar-energy-driven reaction that uses an electron donor source material. Among artificial-photosynthesis processes, inorganic-synthesis reactions oxidation, including splitting CO2-to-fuel conversion, have attracting much attention. contrast, synthesis high-value functionalized organic compounds which we termed directed toward (APOS), remains great challenge. Herein, report synthetically pioneering meaningful strategy APOS, where carbohydroxylation C = double bonds is accomplished three-component coupling with H2 evolution using dual functions semiconductor photocatalysts, i.e., silver-loaded titanium dioxide (Ag/TiO2) rhodium–chromium–cobalt-loaded aluminum-doped strontium titanate (RhCrCo/SrTiO3:Al). Emulating concept long focus chemists effort to harness light Here, authors present photosynthetic system can functionalize styrenes C–H activation splitting.

Language: Английский

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Photochemical Deracemization of Lactams with Deuteration Enabled by Dual Hydrogen Atom Transfer

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 18, 2024

Photochemical deracemization has emerged as one of the most straightforward approaches to access highly enantioenriched compounds in recent years. While excited-state events such energy transfer, single electron and ligand-to-metal charge transfer have been leveraged promote stereoablation, relying on hydrogen atom which circumvent limitations imposed by triplet redox potential racemic substrates, remain underexplored. Conceptually, attractive method for tertiary stereocenter might be abstraction followed donation. However, implementing a strategy poses significant challenges, primarily because products are also reactive if chiral catalyst is unable differentiate between two enantiomers. Herein we report distinct dual photochemical δ- γ-lactams, achieving high enantioenrichment deuterium incorporation despite inherent reactivity products. Mechanistic studies reveal that benzophenone enables nonselective while tetrapeptide-derived thiol dictates enantioselectivity donation step. More importantly, pyridine-based alcohol was found play crucial roles facilitating well enhancing

Language: Английский

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Enantioselective Cobalt-Catalyzed Remote Hydroboration of Alkenylboronates

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

Heteroatomic groups in alkenes typically direct thermodynamically favored chain walking of C═C bonds toward themselves, thereby facilitating C-H bond functionalization near the heteroatoms. We present herein an efficient cobalt-catalyzed contra-thermodynamic remote hydroboration alkenylboronates with pinacolborane to synthesize chiral 1,n-diboronates. This protocol features a broad substrate scope, high functional group tolerance, and excellent enantioselectivity. Mechanistic studies indicate involvement chain-walking process. Gram-scale reactions various product derivatizations further highlight its practicality.

Language: Английский

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Photoenolization of α,β-Unsaturated Esters Enables Enantioselective Contra-Thermodynamic Positional Isomerization to α-Tertiary β,γ-Alkenyl Esters

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(9), P. 7452 - 7460

Published: Feb. 24, 2025

The enantioselective protonation of prochiral enolates is an ideal and straightforward platform to synthesize stereodefined α-tertiary esters, which are recurring motifs in a myriad biorelevant molecules important intermediates thereof. However, this approach remains onerous, particularly when dealing with α-unactivated esters related acids, as enantioinduction on the nascent nucleophile necessitates peremptory reaction conditions, thus far only achieved via preformed enolates. A complementary contra-thermodynamic catalytic strategy herein described, where transient photoenol, form ketene hemiacetal, enantioselectively protonated chiral phosphoric acid (CPA). photoketene hemiacetals procured from excited α,β-unsaturated specifically Z-geometric isomer through [1,5]-hydride shift chemically productive nonradiative relaxation pathway. Tautomerization formal 1,3-proton transfer hemiacetal CPA proton shuttle delivers α-branched β,γ-alkenyl good excellent yields enantioselectivity under mild conditions. Furthermore, current protocol was coupled functional group interconversion experiments, well total synthesis known marine γ-butyrolactone-type metabolite. Performing continuous photoflow setup also enabled gram-scale ester up 92% ee.

Language: Английский

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The role of Kinetic Asymmetry in Chemical and Thermodynamic Coupling

ChemSystemsChem, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 15, 2024

Abstract The input of energy can shift an isomerization reaction A⇌B away from equilibrium, but which way, in favor A or B? answer to this question lies understanding kinetic asymmetry, a concept first discussed the context how oscillating fluctuating perturbation act concert with catalyst drive equilibrium. key theoretical result is non‐equilibrium pumping equality that generalizes idea equilibrium constant steady‐state.

Language: Английский

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Enabling Unfavorable Hydroamination Reactions Using a Chemoselective N–O Bond Reduction

Organic Letters, Journal Year: 2024, Volume and Issue: 26(46), P. 9885 - 9890

Published: Nov. 7, 2024

Despite major advances, intramolecular alkene hydroamination reactions often face limitations. Herein, a redox-enabled process featuring oxidation of an amine to hydroxylamine, concerted step, followed by catalytic reduction

Language: Английский

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Free Alcohol‐Mediated Radical Alkynylation and Allylation of Unactivated C(sp3)‐H Bonds

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 15, 2024

The daunting challenges in converting alcoholic O-H bonds with high bond-dissociation energy (BDE) to alkoxy radicals and harnessing those unruly reaction species largely limit exploiting free alcohols C(sp

Language: Английский

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