Sergiy Pazenok

Recent advances in transition metal-catalyzed Csp2-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

Summary In the last few years, transition metal-mediated reactions have joined the toolbox of chemists working in the field of fluorination for Life-Science oriented research. The successful execution of transition metal-catalyzed carbon–fluorine bond formation has become a landmark achievement in fluorine chemistry. This rapidly growing research field has been the subject of some excellent reviews. Our approach focuses exclusively on transition metal-catalyzed reactions that allow the introduction of –CFH2, –CF2H, –CnF2 n +1 and –SCF3 groups onto sp² carbon atoms. Transformations are discussed according to the reaction-type and the metal employed. The review will not extend to conventional non-transition metal methods to these fluorinated groups.

Trifluoromethyl ethers – synthesis and properties of an unusual substituent

Summary After nitrogen, fluorine is probably the next most favorite hetero-atom for incorporation into small molecules in life science-oriented research. This review focuses on a particular fluorinated substituent, the trifluoromethoxy group, which is finding increased utility as a substituent in bioactives, but it is still perhaps the least well understood fluorine substituent in currency. The present review will give an overview of the synthesis, properties and reactivity of this important substituent.

A Major Advance in the Synthesis of Fluoroalkyl Pyrazoles: Tuneable Regioselectivity and Broad Substitution Patterns

A novel approach towards highly functionalized fluoroalkyl pyrazoles was developed by using fluoroalkyl amino reagents in combination with a variety of fluorinated ketimines. Tuneable introduction of fluoroalkyl groups in the 3- and 5-positions was possible by using vinamidinium intermediates or the corresponding enamino ketones after hydrolysis. These high-value building blocks can give rise to a large number of analogues for bioactivity screening and discovering new heterocyclic bioactive ingredients in various life science fields.

A new approach toward the synthesis of 2,4-bis(fluoroalkyl)-substituted quinoline derivatives using fluoroalkyl amino reagent chemistry

The present work describes the unprecedented use of Fluoroalkyl Amino Reagents (FARs) to afford 2,4-bis(fluoroalkyl)-substituted quinoline derivatives in two steps. In contrast to the Combes reaction, this approach allows for the synthesis of numerous quinoline derivatives bearing two identical or different fluoroalkyl substituents in the 2 and 4 positions, under mild reaction conditions, in good yields and with a very good regioselectivity. This reaction is easily scalable and suitable for an industrial process.

Fluoroalkyl Amino Reagents (FARs): A General Approach towards the Synthesis of Heterocyclic Compounds Bearing Emergent Fluorinated Substituents

Fluorinated heterocycles are important building blocks in pharmaceutical, agrochemical and material sciences. Therefore, organofluorine chemistry has witnessed high interest in the development of efficient methods for the introduction of emergent fluorinated substituents (EFS) onto heterocycles. In this context, fluoroalkyl amino reagents (FARs)—a class of chemicals that was slightly forgotten over the last decades—has emerged again recently and proved to be a powerful tool for the introduction of various fluorinated groups onto (hetero)aromatic derivatives.

Synthesis of Mono‐ and Bis(fluoroalkyl)pyrimidines from FARs, Fluorinated Acetoacetates, and Malononitrile Provides Easy Access to Novel High‐Value Pyrimidine Scaffolds

A new strategy was developed using fluorinated acetoacetates, malononitrile, and fluoroalkyl amino reagents (FARs) to access unprecedented 4,6-bis(fluoroalkyl)pyrimidine-5-carboxylates, their carboxylic acid analogues, and 4-amino-6-(fluoroalkyl)pyrimidine-5-carbonitriles. An efficient cyclization step using suitable amidines was developed under microwave irradiation, providing the desired pyrimidines rapidly and efficiently. Standard saponification conditions were applied from carboxylate derivatives to access to the corresponding carboxylic acids. These new valuable building blocks, bearing either a single or two emergent fluorinated substituents, hold strong potential for medicinal and agrochemical research.

Synthesis of Halogenated 5- and 6-Membered Sulfur- and Sulfur, Nitrogen-Containing Heterocycles

This review describes the data concerning the chemistry of halogenated 5- and 6-membered sulfur- and sulfur, nitrogen-containing heterocycles published in literature since 2000. The only monocyclic derivatives of thiophene, thiazole, thiopyrane, and thiazine with halogens atom(s) or perhalogenoalkyl group directly bound to heterocycle are analyzed. The main attention is paid to the new approaches to the synthesis of these compounds by halogenations of the heterocycle molecule or by the usage of the acyclic halogenated synthons. The consideration of the chemical properties of these heterocycles concentrates mainly on the examples of their usage for the synthesis of compounds with valuable properties, for example biologically active.