Asymmetric enamine catalysis.

Ionic liquids are remarkable chemical compounds, which find applications in many areas of modern science. Because of their highly tunable nature and exceptional properties, ionic liquids have become essential players in the fields of synthesis and catalysis, extraction, electrochemistry, analytics, biotechnology, etc. Apart from physical and chemical features of ionic liquids, their high biological activity has been attracting significant attention from biochemists, ecologists, and medical scientists. This Review is dedicated to biological activities of ionic liquids, with a special emphasis on their potential employment in pharmaceutics and medicine. The accumulated data on the biological activity of ionic liquids, including their antimicrobial and cytotoxic properties, are discussed in view of possible applications in drug synthesis and drug delivery systems. Dedicated attention is given to a novel active pharmaceutical ingredient-ionic liquid (API-IL) concept, which suggests using traditional drugs in ...

Biological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine.

Sustainable solvents are a topic of growing interest in both the research community and the chemical industry due to a growing awareness of the impact of solvents on pollution, energy usage, and contributions to air quality and climate change. Solvent losses represent a major portion of organic pollution, and solvent removal represents a large proportion of process energy consumption. To counter these issues, a range of greener or more sustainable solvents have been proposed and developed over the past three decades. Much of the focus has been on the environmental credentials of the solvent itself, although how a substance is deployed is as important to sustainability as what it is made from. In this Review, we consider several aspects of the most prominent sustainable organic solvents in use today, ionic liquids, deep eutectic solvents, supercritical fluids, switchable solvents, liquid polymers, and renewable solvents. We examine not only the performance of each class of solvent within the context of the...

Green and Sustainable Solvents in Chemical Processes

Asymmetric Organocatalytic Cyclization and Cycloaddition Reactions

Asymmetric aldol reactions are a powerful method for the construction of carbon–carbon bonds in an enantioselective fashion. Historically this reaction has been performed in a stoichiometric fashion to control the various aspects of chemo-, diastereo-, regio- and enantioselectivity, however, a more atom economical approach would unite high selectivity with the use of only a catalytic amount of a chiral promoter. This critical review documents the development of direct catalytic asymmetric aldol methodologies, including organocatalytic and metal-based strategies. New methods have improved the reactivity, selectivity and substrate scope of the direct aldol reaction and enabled the synthesis of complex molecular targets (357 references).

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The Direct Catalytic Asymmetric Aldol Reaction

Organic and hybrid molecular systems

A novel (S)-proline-modified task-specific chiral ionic liquid—an amphiphilic recoverable catalyst for direct asymmetric aldol reactions in water

The review is devoted to the application of organocatalysis for the asymmetric aldol reaction, which is one of the most important methods for carbon–carbon bond formation in organic compounds The mechanism of enamine catalysis and the main types of organocatalysts for the aldol reaction are considered, data on this type of reactions involving carbonyl compounds with various electronic and spatial structures are classified The effects of organocatalyst structure on the regio-, stereo- and enantioselectivity of intramolecular and intermolecular aldol reactions are reviewed

https://iopscience.iop.org/article/10.1070/RC2009v078n08ABEH004040/pdf

Organocatalysis of asymmetric aldol reaction. Catalysts and reagents

Stereoselective reactions of nitro compounds in the synthesis of natural compound analogs and active pharmaceutical ingredients

The prevalence of nitrogen containing heterocycles in natural products and pharmaceuticals is a doubtless fact. In this review, recent applications of a stereoselective aza-Michael reaction as an efficient tool for the asymmetric synthesis of naturally occurring nitrogen-containing heterocyclic scaffolds and their usefulness to pharmacology are reviewed and summarized. The available data are for the first time classified according to types of heterocyclic products and subdivided in accordance with synthetic methodologies used as key stereocontrolling steps (diastereoselective or enantioselective reactions, single bond-forming or cascade reactions, etc.). This classification is convenient for organic chemists and for researchers working in the areas of natural product synthesis and medicinal chemistry. Specific attention is paid to organocatalytic asymmetric versions of the aza-Michael reaction developed over the past decade.

Sergei G. Zlotin

Papers

Organic and hybrid molecular systems

A novel (S)-proline-modified task-specific chiral ionic liquid—an amphiphilic recoverable catalyst for direct asymmetric aldol reactions in water

Organocatalysis of asymmetric aldol reaction. Catalysts and reagents

Stereoselective reactions of nitro compounds in the synthesis of natural compound analogs and active pharmaceutical ingredients

Recent advances in the asymmetric synthesis of pharmacology-relevant nitrogen heterocycles via stereoselective aza-Michael reactions.