KOSEN 한인과학기술자네트워크

Fluoroalkylations 

• Visible-light photoredox catalysis has been proved to be a powerful preparative tool owing to its environmental benignity and mechanistic versatility in promoting a large number of synthetically important reactions with high levels of selectivity. Pertaining to their unique biological, physical, and chemical properties, ？uoroalkylated organic substances have attracted signi？cant attention from researchers in a variety of disciplines. Fluoroalkylated compounds are considered particularly important in pharmaceutical chemistry because of their superior lipophilicity, binding selectivity, metabolic stability, and bioavailability to those of their non？uoroalkylated analogues. Our group has continuously been involved in the development of various methods for the synthesis of ？uoroalkylated substances that rely on the use of visible-light photoredox catalysis. We developed visible-light photocatalytic methods for the introduction of a variety of ？uoroalkyl groups (such as, −CF₃, −CF₂R, −CH₂CF₃, −C₃F₇, and −C₄F₉) arylthio？uoroalkyl groups (such as, −CF₂SPh, −C₂F₄SAr, and −C₄F₈SAr) and oxyfluoroalkyl groups (such as, −CF₂OPh, and –(CF₂)₂OPh) to organic substances. We are continuously striving for the development of state-of-the-art fluorination and fluoroalkylation methods under mild reaction conditions. 

Heterocycle Synthesis

• Heterocycles are tremendously important structures in chemistry. They are present in countless compounds of interest, such as drugs, agrochemicals, natural products, as well as in the basic building blocks of life like nucleic acids and sugars. Because of their importance and the diversity of their structures, our group has been making significant research effort to develop new methods for the de novo construction of heterocycles and their subsequent functionalisation to prepare derivatives. Our group has developed methods for the construction of highly valuable heterocyclic rings such as benzothiazoles, benzimidazoles, carbazoles, dibenzofurans, fused bi and tricyclic system of tetrahydropyrrole and oxadiazoles, poly (hetero)aromatic ring system, spiro(hetero)cyclic compounds. Very recently our group has contributed towards the synthesis of highly functionalized quinoline building block under white light irradiation.

Redox Reactions 

• In living systems, enzyme-catalyzed reactions are involved in a large number of pathways leading to structurally diverse and complex natural products. Among these enzymatic reactions oxidation-reduction (redox) reactions are important because they are the principal sources of energy. These reactions are the fundamental reactions in nature and has always been of great interest in synthetic organic chemistry. The efficiencies and mild nature of these enzymatic processes have encouraged organic chemists to develop transformations which mimic those promoted by enzymes. These methods mostly involve the transformation or interconversion of the functional groups. Our group has developed a variety of redox synthetic methods for example, transformation of aldehydes to carboxylic acids and amides, and oxidation of amine to aldehydes by oxidative C-N bond cleavage. Furthermore, we have reported the transformation of a-bromo ketones to a-hydroxy ketone and homocoupled product of benzyl bromide.