Recent Developments and Trends in Asymmetric Organocatalysis

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 26(1)

Published: Oct. 17, 2022

Asymmetric organocatalysis has experienced a long and spectacular way since the early reports over century ago by von Liebig, Knoevenagel Bredig, showing that small (chiral) organic molecules can catalyze (asymmetric) reactions. This was followed impressive first highly enantioselective in second half of last century, until hype initiated 2000 milestone publications MacMillan List, which finally culminated 2021 Nobel Prize Chemistry. short Perspective aims at providing brief introduction to field looking on historical development more classical methods concepts, discussing selected advanced recent examples opened new directions diversity within this still growing field.

Language: Английский

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Catalytic asymmetric cationic shifts of aliphatic hydrocarbons

Nature, Journal Year: 2024, Volume and Issue: 625(7994), P. 287 - 292

Published: Jan. 10, 2024

Abstract Asymmetric catalysis is an advanced area of chemical synthesis, but the handling abundantly available, purely aliphatic hydrocarbons has proven to be challenging. Typically, heteroatoms or aromatic substructures are required in substrates and reagents facilitate efficient interaction with chiral catalyst. Confined acids have recently been introduced as tools for homogenous asymmetric catalysis, specifically enable processing small unbiased 1 . However, reactions which both substrate product not previously catalysed by such super strong confined acids. We describe here imidodiphosphorimidate-catalysed Wagner–Meerwein shift alkenyl cycloalkanes cycloalkenes excellent regio- enantioselectivity. Despite their long history high relevance synthesis biosynthesis, utilizing hydrocarbons, those originally reported Wagner Meerwein, had eluded catalysis.

Language: Английский

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The green chemistry paradigm in modern organic synthesis

Russian Chemical Reviews, Journal Year: 2023, Volume and Issue: 92(12), P. RCR5104 - RCR5104

Published: Dec. 1, 2023

After the appearance of green chemistry concept, which was introduced in vocabulary early 1990s, its main statements have been continuously developed and modified. Currently, there are 10–12 cornerstones that should form basis for an ideal chemical process. This review analyzes accumulated experience achievements towards design products processes reduce or eliminate use generation hazardous substances. The presents views leading Russian scientists specializing various fields this subject, including homogeneous heterogeneous catalysis, fine basic organic synthesis, electrochemistry, polymer chemistry, based on bio-renewable feedstocks energetic compounds materials. A new approach to quantitative evaluation environmental friendliness by authors is described. <br> bibliography includes 1761.

Language: Английский

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Evolution of Pyrrolysyl-tRNA Synthetase: From Methanogenesis to Genetic Code Expansion

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(16), P. 9580 - 9608

Published: July 2, 2024

Over 20 years ago, the pyrrolysine encoding translation system was discovered in specific archaea. Our Review provides an overview of how once obscure pyrrolysyl-tRNA synthetase (PylRS) tRNA pair, originally responsible for accurately translating enzymes crucial methanogenic metabolic pathways, laid foundation burgeoning field genetic code expansion. primary focus is discussion to successfully engineer PylRS recognize new substrates and exhibit higher

Language: Английский

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Electrochemical Asymmetric Radical Functionalization of Aldehydes Enabled by a Redox Shuttle

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(25)

Published: April 16, 2024

Aminocatalysis is a well-established tool that enables the production of enantioenriched compounds under mild conditions. Its versatility underscored by its seamless integration with various synthetic approaches. While combination aminocatalysis metal catalysis, photochemistry, and stoichiometric oxidants has been extensively explored, synergy electrochemical activation remains largely unexplored. Herein, we present successful merger electrochemistry to perform SOMO-type transformations, expanding toolkit for asymmetric synthesis. The methodology harnesses electricity drive oxidation catalytically generated enamines, which ultimately partake in enantioselective radical processes, leading α-alkylated aldehydes. Crucially, mechanistic studies highlight how this strategy enabled use redox shuttle, 4,4'-dimethoxybiphenyl, prevent catalyst degradation furnishing coveted good yield high enantioselectivity.

Language: Английский

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Catalytic Enantioselective Synthesis of Inherently Chiral Calix[4]arenes via Sequential Povarov Reaction and Aromatizations

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(45)

Published: July 8, 2024

Inherently chiral calix[4]arenes represent a unique type of molecules with significant applications, yet their catalytic enantioselective synthesis remains largely underexplored. We report herein the inherently through sequential organocatalyzed Povarov reaction and aromatizations. The phosphoric acid catalyzed three-component involving amino group-substituted calix[4]arenes, aldehydes (di)enamides desymmetrized prochiral calix[4]arene substrates, which was followed by various aromatization methods, resulting in diverse array novel quinoline-containing good yields high enantioselectivities (up to 75 % yield, 99 ee). large-scale derivatizations products highlight value this method. Furthermore, preliminary exploration into photophysical chiroptical properties demonstrate potential applications these molecules.

Language: Английский

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Enantioselective organocatalytic strategies to access noncanonical α-amino acids

Chemical Science, Journal Year: 2024, Volume and Issue: 15(16), P. 5832 - 5868

Published: Jan. 1, 2024

Organocatalytic asymmetric synthesis has evolved over the years and continues to attract interest of many researchers worldwide. Enantiopure noncanonical amino acids (ncAAs) are valuable building blocks in organic synthesis, medicinal chemistry, chemical biology. They employed elaboration peptides proteins with enhanced activities and/or improved properties compared their natural counterparts, as chiral catalysts, ligand design, for syntheses complex molecules, including products. The linkage ncAA enantioselective organocatalysis, subject this perspective, tries imitate biosynthetic process. Herein, we present contemporary earlier developments field organocatalytic activation simple feedstock materials, providing potential ncAAs diverse side chains, unique three-dimensional structures, a high degree functionality. These strategies, useful forging wide range C-C, C-H, C-N bonds combinations thereof, vary from classical name reactions, such Ugi, Strecker, Mannich most advanced concepts deracemisation, transamination, carbene N-H insertion. Concurrently, some interesting mechanistic studies/models, information on chirality transfer Finally, perspective highlights, through diversity (AAs) not selected by nature protein incorporation, generic modes activation, induction, reactivity commonly used, enamine, hydrogen bonding, Brønsted acids/bases, phase-transfer reflecting increasingly important role applied chemistry.

Language: Английский

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Photochemical Wolff Rearrangement Initiated Generation and Subsequent α-Chlorination of C1 Ammonium Enolates

Organic Letters, Journal Year: 2023, Volume and Issue: 25(17), P. 3126 - 3130

Published: April 25, 2023

The enantioselective synthesis of α-chlorinated carboxylic acid esters with er up to 99:1 and yields 82% was achieved via a one-pot multistep protocol starting from α-diazoketones. This process proceeds photochemical Wolff rearrangement, trapping the generated ketene chiral Lewis base catalyst, subsequent α-chlorination, final nucleophilic displacement bound catalyst. obtained products were successfully utilized for stereospecific reactions N- S-nucleophiles.

Language: Английский

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A robust heterogeneous chiral phosphoric acid enables multi decagram scale production of optically active N,S-ketals

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(8), P. 4593 - 4599

Published: Jan. 1, 2024

A multi-decagram scale synthesis of enantioenriched N,S -ketals was achieved by using a robust heterogeneous organocatalyst. new reactor design crucial to enable the scaling up this reaction while overall catalyst loading below 0.1%.

Language: Английский

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Organocatalytic Transformations from Sulfur Ylides

Catalysts, Journal Year: 2023, Volume and Issue: 13(4), P. 689 - 689

Published: March 31, 2023

Sulfur ylides are an important class of organic compounds due to their ability perform many different transformations that can give diverse and interesting products with a high degree complexity. Although metal-catalyzed frequent in this compounds, organocatalyzed remain scarce. From initial works, review aims show from sulfur ylides, involving cyclopropanation formal N–H, S–H, C–H insertion reactions, including enantioselective versions. The proposed mechanisms the modes activation these organocatalysts will be covered. Furthermore, advances area potential challenges circumvented near future also discussed.

Language: Английский

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