Chiral Organoselenium Research Articles

Asymmetric Synthesis and Applications of Chiral Organoselenium Compounds: A Review.

The synthesis and application of organoselenium compounds have developed rapidly, and chiral organoselenium compounds have become an important intermediate in the field of medicine, materials, organic synthesis. The strategy of developing a green economy is still a challenge in the synthesis of chiral organoselenium compounds with enantioselective properties. This review covers in detail the synthesis of chiral organoselenium compounds from 1979 to 2024 and their application in the fields of asymmetric synthesis and catalysis.

Organoselenium-Catalyzed Enantioselective Synthesis of 2-Oxazolidinones from Alkenes.

An operationally simple method for generating enantioenriched 2-oxazolidinones from N-Boc amines and mono- or trans-disubstituted alkenes via chiral organoselenium catalysis is described. Critical to the success of the transformation was the inclusion of triisopropylsilyl chloride (TIPSCl), likely because it sequestered fluoride generated by the oxidant (N-fluorocollidinium tetrafluoroborate) throughout the reaction and suppressed side reactivity. The scope of both the amine and alkene substrates was explored, generating a variety of 2-oxazolidinones in modest to high yields with high enantioselectivities.

Recent Progress in Synthesis and Application of Chiral Organoselenium Compounds.

Chiral organoselenium compounds have shown an important role as intermediates in many areas, such as drug discovery, organic catalysis, and nanomaterials. A lot of different methods have been developed to synthesize chiral compounds which contain selenium, because they have interesting properties and can be used in real life. Over the last few decades, a lot of progress has been made in synthesizing chiral organoselenium compounds. This work gives an overview of the progress made in creating new ways to synthesize chiral organoselenium compounds by categorizing them into groups based on the reactions they undergo. In addition, the use of chiral organoselenium compounds is also discussed.

Asymmetric Catalysis of Chiral Bifunctional Selenides and Selenonium Salts Bearing a Urea Group

AbstractCatalytic asymmetric reactions with chiral organoselenium catalysts have become one of the most important research topics in the field of organocatalysis. Despite the presence of several effective chiral selenium catalysts, further developments of new chiral organoseleniums are still desired due to their remarkable potential as asymmetric organocatalysts. Herein, we report the synthesis and asymmetric catalysis of chiral bifunctional selenides and selenonium salts bearing a urea group. The new chiral bifunctional selenide organocatalysts promote asymmetric halocyclizations with good to high levels of enantioselectivity. Furthermore, we report a reaction involving a precious example of a chiral tertiary selenonium salt‐catalyzed asymmetric phase‐transfer conjugate addition.

Selenium and Tellurium Electrophiles in Organic Synthesis

Abstract This chapter highlights the utility of electrophilic achiral and chiral organoselenium reagents in organic synthesis. A range of reactions from alkene functionalizations, the functionalization of aliphatic and aromatic C–H bonds using stoichiometric and catalytic approaches as well as rearrangement reactions are described. In addition, the utility of organotellurium reagents in organic synthesis is covered in this chapter.

Synthesis of l-Selenocysteine and α-Methyl-l-Selenocysteine Derivatives Using Woollins’ Reagent and Their Application as Chiral Selenium Catalysts

The reaction of oxazolines, which were synthesized from l-serine methyl ester, with Woollins’ reagent in refluxing acetonitrile for 2 h and subsequent treatment of the crude products with sodium borohydride gave l-selenocysteine derivatives in up to 82 % yield without occurring racemization. Similar reaction protocols were applied for α-methyl-l-serine derivatives to afford various optically pure α-methyl-l-selenocysteine derivatives in moderate yields (~43 %). The obtained α-methylselenocysteine derivatives were applied as a catalyst for asymmetric cyclization of β,γ-unsaturated acids to α,β-unsaturated lactones in the presence of ammonium persulfate. The highest optical yield (27 % e.e.) was achieved when N,N′-diacetyl-α,α′-dimethyl-l-selenocystine diethyl ester was employed as a catalyst. Thus, potential usability of selenoamino acid derivatives as chiral organoselenium catalysts was demonstrated.

Conformational analysis and diastereotopic assignments in the series of selenium‐containing heterocycles by means of 77Se‐1H spin‐spin coupling constants: a combined theoretical and experimental study

A combined theoretical and experimental study on the stereochemical behavior of (77)Se-(1)H spin-spin coupling constants has been performed at the second-order polarization propagator approach level together with heteronuclear multiple-bond correlation technique in the series of selenium-containing four-, five- and six-membered heterocycles including the derivatives of thiaselenetane, selenasilole, thiaselenole, thiaselenolane and dihydrothiaselenine. Geminal and vicinal (77)Se-(1)H spin-spin couplings were shown to have the pronounced stereochemical dependences in respect with the topology of the coupling pathway, internal rotation of the side-chain substituents and ring inversion providing a straightforward tool for the conformational analysis and diastereotopic assignments in the chiral organoselenium compounds.

First chemoenzymatic synthesis of organoselenium amines and amides

A series of organoselenium amines have been synthesized and submitted to the enzymatic kinetic resolution by acetylation mediated by CAL-B (Novozym 435) to give the corresponding chiral amides in an enantiomerically pure form. After evaluating the appropriate lipase, solvent, temperature, and lipase/substrate ratio in the kinetic resolution, the chiral organoselenium amides were obtained with enantiomeric excess of up to 99%.

Enantioselective Synthesis Mediated by Catalytic Chiral Organoselenium Compounds

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Asymmetric Synthesis of Chiral Organoselenium Compounds

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Asymmetric Synthesis of Chiral Organoselenium Compounds

Chiral organoselenium compounds can be attained from three types of asymmetric synthesis. Chiral substratecontrolled methods, chiral auxiliary-controlled methods, and chiral catalyst-controlled methods toward optically active organoselenium derivatives were illustrated. The strategy and classification of methods underlying all asymmetric synthesis therefore involve enantiomerically pure compounds to influence the stereochemical outcome of the reactions. In this review, the advances in asymmetric synthesis of some important classes of chiral organoselenium compounds were described. Keywords: Prochiral Olefin, Selenocyclization, regioselectivity, ammonium persulfate, Seleno Alcohols

Enantioselective Synthesis Mediated by Catalytic Chiral Organoselenium Compounds

Selenium-based methods have developed rapidly over the past few years and certain features of chiral selenium-containing compounds make these reagents particularly valuable for efficient stereoselective reactions. Recent advances in stereoselective transformations involving one-pot selenenylation-deselenylation sequences, which occur using only catalytic amounts of the optically active diselenides in the synthesis of valuable building blocks will be summarized. Additionally, recent results of catalytic reactions using chiral selenides and diselenides such as the enantioselective copper catalyzed conjugate addition of organometallic reagents to enones, diorganozinc addition to aldehydes, palladium-catalyzed enantioselective allylic alkylation, among other topics will also be addressed.

Catalytic Applications of Chiral Organoselenium Compounds in Asymmetric Synthesis

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Catalytic Applications of Chiral Organoselenium Compounds in Asymmetric Synthesis

Chiral selenium-containing compounds have found growing application in asymmetric catalysis over the past few years. The large majority of these ligands are derived from readily available chiral amino alcohols in a few high-yielding synthetic steps. The advantages of using these compounds are described, particularly those regarding ready accessibility, modular nature, formation of strong bonds with soft metals and more rarely with hard ones. By using an appropriate electrophilic or nucleophilic organoseleni- um fragment, novel chiral organoselenium catalysts or ligands were designed from chiral aziridines, oxazolines, ferrocenes, etc. High regioselectivity and enantioselectivity were achieved through the four following techniques: the enantioselective copper-catalyzed conjugate addition of organometallic reagents to enones, the diorga- nozinc addition to aldehydes, palladium-catalyzed enantioselective allylic alkylation and asymmetric hydrosilylation or transfer hydro- genations of ketones.

Asymmetric Baeyer—Villiger Oxidation of Cyclic Ketones Using Chiral Organoselenium Catalysts.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Asymmetric Baeyer–Villiger Oxidation of Cyclic Ketones Using Chiral Organoselenium Catalysts

Abstract Novel optically active diselenides having a chiral oxazoline have been prepared and the structure of one of them is unambiguously determined by X-ray structural analysis. Treatment of a variety of cyclobutanones with 30% H2O2 in the presence of a catalytic amount of the optically active diselenides in tetrahydrofuran or 1,4-dioxane at 0 °C–rt affords the corresponding γ-lactones in up to 92% yield with up to 19% ee. The enantioselectivity of the product is not yet satisfactory, but this is the first example of asymmetric Baeyer–Villiger oxidation catalyzed by chiral organoselenium compounds.

ChemInform Abstract: Asymmetric Arene—Alkene Cyclizations Mediated by a Chiral Organoselenium Reagent.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Asymmetric arene-alkene cyclizations mediated by a chiral organoselenium reagent

Asymmetric arene-alkene cyclization reactions mediated by a chiral electrophilic organoselenium reagent afforded substituted carbocyclic derivatives with high diastereoselectivities. It was also found that β-methoxyselenides are good precursors of seleniranium ions when treated with strong acids.