Enantioselective desymmetrization reactions in asymmetric catalysis

Tetrahedron, Journal Year: 2022, Volume and Issue: 106-107, P. 132629 - 132629

Published: Jan. 1, 2022

Language: Английский

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A tutorial on asymmetric electrocatalysis

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(23), P. 8106 - 8125

Published: Jan. 1, 2023

This tutorial review delves into the unique advantages of electrochemistry in context asymmetric catalysis, first providing a brief introduction to electrosynthesis, then exploring representative case studies with mechanistic focus.

Language: Английский

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Peptidomics

Nature Reviews Methods Primers, Journal Year: 2023, Volume and Issue: 3(1)

Published: March 30, 2023

Language: Английский

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Salient Achievements in Synthetic Organic Chemistry Enabled by Mechanochemical Activation

Synthesis, Journal Year: 2023, Volume and Issue: 55(16), P. 2439 - 2459

Published: May 3, 2023

Abstract Although known for millennia, it is only recently that mechanochemistry has received serious attention by chemists. Indeed, during the past 15 years an extraordinary number of reports concerning solid-state chemical transformations through grinding and milling techniques have been recorded. This short review discusses circumstances led this renaissance, highlighting present intense interest in so-called green chemistry, enabling capacity to handle insoluble substrates, identification profound influence additives can on mechanochemically activated reactions. The core account focuses salient developments synthetic organic especially amino acid peptide­ mechanosynthesis, successful employment mechanochemical activation combination with asymmetric organocatalysis, promising enzymatic whole cell biocatalysis, remarkable achievement multicomponent selective reactions via complex, multistep reaction pathways, mechanosynthesis representative heterocycles. final section comments some pending tasks area, such as scaling-up processes be practical use industry, requirement easier more efficient control parameters monitoring devices, consequently careful analysis additional procedures a proper understanding phenomena. 1 Introduction 2 Brief History Mechanochemistry 3 Milling Equipment Reaction Parameters 4 Attributes That Propelled Its Present Renaissance 4.1 Enormous Attention Being Presently Paid Sustainable Chemistry 4.2 Reduced Energy Consumption 4.3 Additive-Based 4.4 Handling Insoluble Reactants 4.5 ‘Impossible’ Reactions Are Successful 4.6 Air- Water-Sensitive Reagents Ball 5 Salient Developments Mechanochemical Activation Synthetic Organic 5.1 Amino Acid Peptide Mechanosynthesis 5.2 Asymmetric Synthesis Organocatalysis under Ball-Milling Conditions 5.3 Mechanoenzymology 5.4 Multicomponent Activated 5.5 Heterocycles Modification 6 Future Directions 6.1 Scaling-Up Protocols 6.2 Temperature-Controlled 6.3 Understanding Transformations 6.4 Emerging Techniques 7 Conclusions

Language: Английский

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Generality-oriented optimization of enantioselective aminoxyl radical catalysis

Science, Journal Year: 2023, Volume and Issue: 380(6646), P. 706 - 712

Published: May 18, 2023

Catalytic enantioselective methods that are generally applicable to a broad range of substrates rare. We report strategy for the oxidative desymmetrization

Language: Английский

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Carbene organic catalytic planar enantioselective macrolactonization

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Feb. 1, 2024

Macrolactones exhibit distinct conformational and configurational properties are widely found in natural products, medicines, agrochemicals. Up to now, the major effort for macrolactonization is directed toward identifying suitable carboxylic acid/alcohol coupling reagents address challenges associated with macrocyclization, wherein stereochemistry of products usually controlled by substrate's inherent chirality. It remains largely unexplored using catalysts govern both macrolactone formation stereochemical control. Here, we disclose a non-enzymatic organocatalytic approach construct macrolactones bearing chiral planes from achiral substrates. Our strategy utilizes N-heterocyclic carbene (NHC) as potent acylation catalyst that simultaneously mediates macrocyclization controls planar chirality during catalytic process. varying ring sizes sixteen twenty members obtained good-to-excellent yields enantiomeric ratios. study shall open new avenues accessing various stereogenic elements structures readily available small-molecule catalysts.

Language: Английский

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Controlling Stereoselectivity with Noncovalent Interactions in Chiral Phosphoric Acid Organocatalysis

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: March 18, 2025

Chiral phosphoric acids (CPAs) have emerged as highly effective Brønsted acid catalysts in an expanding range of asymmetric transformations, often through novel multifunctional substrate activation modes. Versatile and broadly appealing, these benefit from modular tunable structures, compatibility with additives. Given the unique types noncovalent interactions (NCIs) that can be established between CPAs various reactants─such hydrogen bonding, aromatic interactions, van der Waals forces─it is unsurprising catalyst systems become a promising approach for accessing diverse chiral product outcomes. This review aims to provide in-depth exploration mechanisms by which impart stereoselectivity, positioning NCIs central feature connects broad spectrum catalytic reactions. Spanning literature 2004 2024, it covers nucleophilic additions, radical atroposelective bond formations, highlighting applicability CPA organocatalysis. Special emphasis placed on structural mechanistic features govern CPA-substrate well tools techniques developed enhance our understanding their behavior. In addition emphasizing details stereocontrolling elements individual reactions, we carefully structured this natural progression specifics broader, class-level perspective. Overall, findings underscore critical role catalysis significant contributions advancing synthesis.

Language: Английский

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Data Science Meets Physical Organic Chemistry

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(16), P. 3136 - 3148

Published: Aug. 5, 2021

ConspectusAt the heart of synthetic chemistry is holy grail predictable catalyst design. In particular, researchers involved in reaction development asymmetric catalysis have pursued a variety strategies toward this goal. This driven by both pragmatic need to achieve high selectivities and inability readily identify why certain effective for given reaction. While empiricism intuition dominated field since its inception, enantioselectivity offers mechanistically rich platform interrogate catalyst-structure response patterns that explain performance particular or substrate.In early stages an campaign, overarching mechanism reaction, speciation, turnover limiting step, many other details are unknown posited based on related reactions. Considering unclear leading successful initial data often used intuitively guide ultimate direction optimization. However, if conditions Curtin–Hammett principle satisfied, then measured can be directly connected ensemble diastereomeric transition states (TSs) lead enantiomeric products, associated free energy difference between competing TSs (ΔΔG⧧ = −RT ln[(S)/(R)], where (S) (R) represent concentrations products). We, others, speculated important piece information leveraged optimization quantitative way.Although traditional linear relationships (LFERs), such as Hammett plots, been illuminate mechanistic features, we sought develop science derived tools expand power LFERs order describe complex reactions frequently encountered modern catalysis. Specifically, investigated whether from quantitatively attributes components, substrate structural harness design.In context, developed workflow relate computationally features components using tools. The mathematical representation molecules incorporate aspects transformation, molecular substrate, product, catalyst, proposed states. Statistical models relating these outputs various tasks, prediction untested molecules. Perhaps most importantly, statistical generation hypotheses embedded within responses. Overall, merging physical organic experiments with modeling techniques creates feedback loop enables evaluation multiple future Account, highlight evolution application approach context collaborative program chiral phosphoric acid catalysts (CPAs)

Language: Английский

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Photochemical Deracemization of Primary Allene Amides by Triplet Energy Transfer: A Combined Synthetic and Theoretical Study

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(29), P. 11209 - 11217

Published: July 19, 2021

The photochemical deracemization of 2,4-disubstituted 2,3-butadienamides (allene amides) was investigated both experimentally and theoretically. reaction catalyzed by a thioxanthone which is covalently linked to chiral 1,5,7-trimethyl-3-azabicyclo[3.3.1]nonan-2-one skeleton providing U-shaped arrangement the sensitizing unit relative potential hydrogen-bonding site. Upon irradiation at λ = 420 nm in presence sensitizer (2.5 mol %), amides reached −10 °C photostationary state one enantiomer prevailed. enantioenriched allene (70–93% ee) were isolated 74% quantitative yield (19 examples). Based on luminescence data DFT calculations, energy transfer from thermodynamically feasible, achiral triplet intermediate structurally characterized. Hydrogen bonding amide enantiomers monitored NMR titration. experimental association constants (Ka) similar (59.8 vs 25.7 L·mol–1). however, revealed significant difference binding properties two enantiomers. major product exhibits noncovalent dispersion interaction its arylmethyl group external benzene ring thioxanthone, thus moving away carbonyl chromophore. minor displays CH−π hydrogen atom terminal carbon same ring, forcing into close proximity behavior explains observed enantioselectivity which, as corroborated additional due rapid within substrate-catalyst complex enantiomer.

Language: Английский

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Catalytic asymmetric and stereodivergent oligonucleotide synthesis

Science, Journal Year: 2021, Volume and Issue: 371(6530), P. 702 - 707

Published: Feb. 11, 2021

We report the catalytic stereocontrolled synthesis of dinucleotides. have demonstrated, for first time to our knowledge, that chiral phosphoric acid (CPA) catalysts control formation stereogenic phosphorous centers during phosphoramidite transfer. Unprecedented levels diastereodivergence also been enabling access either phosphite diastereomer. Two different CPA scaffolds proven be essential achieving stereodivergence: peptide-embedded phosphothreonine-derived CPAs, which reinforce and amplify inherent substrate preference, C2-symmetric BINOL-derived completely overturn this stereochemical preference. The presently reported method does not require stoichiometric activators or auxiliaries enables asymmetric catalysis with readily available phosphoramidites. was applied diastereomeric dinucleotides as well cyclic dinucleotides, are broad interest in immuno-oncology agonists stimulator interferon genes (STING) pathway.

Language: Английский

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