Organoselenium Compounds: Chemistry and Applications in Organic Synthesis

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(52)

Published: June 28, 2023

Abstract Selenium, originally described as a toxin, turns out to be crucial trace element for life that appears selenocysteine and its dimer, selenocystine. From the point of view drug developments, selenium‐containing drugs are isosteres sulfur oxygen with advantage presence selenium atom confers antioxidant properties high lipophilicity, which would increase cell membrane permeation leading better oral bioavailability. In this article, we have focused on relevant features atom, above all, corresponding synthetic approaches access variety organoselenium molecules along proposed reaction mechanisms. The preparation biological selenosugars, including selenoglycosides, selenonucleosides, selenopeptides, other compounds will treated. We attempted condense most important aspects interesting examples chemistry into single article.

Language: Английский

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Regioselective [3+2]‐Spiroannulation and [4+n]‐Annulation Approaches through Activation of C−H Bond Facilitated by Ru(II) as Catalyst: Role of Solvent Selectivity

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(8), P. 1863 - 1876

Published: Feb. 21, 2024

Abstract Ru(II)‐catalyzed and solvent‐switched [3+2]‐spiroannulation [4+n] (n=1, 2, 3) annulations of 2‐aryl quinazolinone or 2‐aryl‐2,3‐dihydrophthalazine‐1,4‐diones with ynones alkynyl alcohol 1,3‐diynes under mild reaction conditions have been analyzed. These reactions take place in the presence appropriate solvent features a redox‐neutral pathway. Ynone serves as an ‘atypical one‐carbon unit’ [4+1] annulation generates tetrasubstituted carbon center bearing diverse heterocycles through [3+2] strategies. Post transformations synthesized spiro‐products augments potential developed methodology.

Language: Английский

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Oxone-Promoted Synthesis of 4-(Chalcogenyl)isoquinoline-N-oxides from Alkynylbenzaldoximes and Diorganyl Dichalcogenides

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 86(2), P. 1721 - 1729

Published: Dec. 31, 2020

We report a protocol for the synthesis of 3-organyl-4-(organylchalcogenyl)isoquinoline-2-oxides via electrophilic cyclization between alkynylbenzaldoximes and diorganyl dichalcogenides promoted by Oxone. A total 21 were selectively obtained in yields up 93% under an ultrasound irradiation condition short reaction times (10–70 min). Additionally, synthetic usefulness 3-phenyl-4-(phenylselanyl)isoquinoline-2-oxide was demonstrated annulation with 1-(2-bromophenyl)-3-phenylprop-2-yn-1-one deoxygenation phenylboronic acid.

Language: Английский

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Recent Progress in Enolonium Chemistry under Metal‐Free Conditions

The Chemical Record, Journal Year: 2021, Volume and Issue: 22(1)

Published: Aug. 21, 2021

Abstract Umpolung approach through inversion of the polarity conventional enolates, has opened up an unprecedented opportunity in cross‐coupling via alkylation. The enolonium equivalents can be accessed either by hypervalent iodine reagents, activation/oxidation amides, or oxidation alkynes. Under umpolung conditions, highly basic conditions required for classical enolate chemistry avoided, and they couple with unmodified nucleophiles such as heteroatom donors electron‐rich arenes.

Language: Английский

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Copper(I)-Catalyzed Formation of Isoquinoline and Quinoline Substituted Isobenzofurans

Organic Letters, Journal Year: 2022, Volume and Issue: 24(15), P. 2899 - 2904

Published: April 11, 2022

An efficient synthetic organic transformation was developed to access isoquinoline-substituted isobenzofurans by reaction of substituted 1,5-diynes with isoquinoline N-oxides. Moderate excellent yields isoquinoline-derived were achieved formation a new C–C and two C–O bonds in the presence copper catalyst one pot. whereas quinoline-substituted obtained when conducted using quinoline N-oxides catalyst.

Language: Английский

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Catalyst- and Additive-Free Annulation of Ynediones and (Iso)Quinoline N-Oxides: An Approach to Synthesis of Pyrrolo[2,1-a]Isoquinolines and Pyrrolo[1,2-a]Quinolines

The Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 86(1), P. 169 - 177

Published: Nov. 30, 2020

A simple and effective annulation of ynediones (iso)quinoline N-oxides was developed to afford various functionalized pyrrolo[2,1-a]isoquinolines pyrrolo[1,2-a]quinolines in moderate excellent yields. This protocol underwent a tandem [3 + 2] cycloaddition/ring-opening/N-nucleophilic addition, which exhibited high regioselectivity, broad substrate tolerance, atom economy under catalyst-, additive-free, air conditions. Moreover, indolizine also successfully prepared using pyridine N-oxide.

Language: Английский

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Cu^II-Catalyzed Coupling with Two Ynone Units by Selective Triple and Sigma C–C and C–H Bond Cleavages

Organic Letters, Journal Year: 2021, Volume and Issue: 23(5), P. 1928 - 1933

Published: Feb. 11, 2021

We report a new copper-catalyzed [2 + 2 1] annulation process through the selective cleavage of sigma and triple C–C C–H bonds using two ynone units. This methodology involves breaking multiple chemical in single operation, including C≡C, C–C, C–H, N–O. These high-value adducts lead to diverse collection synthetically challenging trisubstituted indolizines by simultaneous engagement different bond-breaking events show excellent fluorescence green aqueous solutions.

Language: Английский

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Phosphine-Catalyzed Synthesis of 3-Allyl-4-pyrones by the Tandem Reaction of Diynones and Allylic Alcohols

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 86(21), P. 14476 - 14484

Published: Oct. 18, 2021

A simple and effective tandem reaction of diynones allylic alcohols was developed to afford functionalized 3-allyl-4-pyrones in moderate excellent yields. This protocol underwent a Michael addition─Claisen rearrangement─O-cyclization process, which exhibited broad substrate tolerance, high regioselectivity, atom economy under metal-free condition. Moreover, functional transformation the products also further studied.

Language: Английский

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Base-Promoted Decarboxylative Annulation of Methyl 2-(2-Bromophenyl)acetates and Ynones to Access Benzoxepines

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(5), P. 3079 - 3088

Published: Feb. 17, 2023

A simple and efficient base-mediated decarboxylative annulation of ynones with methyl 2-(2-bromophenyl)acetates has been developed. broad range benzoxepines were prepared a substrate scope high regioselectivity in moderate to excellent yields under transition-metal-free conditions. This method proceeds through tandem [2 + 4] annulation, ring-opening reaction, the intramolecular nucleophilic aromatic substitution reaction. Additionally, key intermediates successfully obtained characterized unambiguously by single-crystal X-ray crystallography, which could favorably support mechanism. Furthermore, gram-scale reaction synthetic applications for further functionalization are also studied.

Language: Английский

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Ag(I)-Mediated Annulation of 2-(2-Enynyl)pyridines and Propargyl Amines to Access 1-(2H-Pyrrol-3-yl)indolizines

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 89(1), P. 304 - 312

Published: Dec. 21, 2023

An effective Ag(I)-mediated annulation of 2-(2-enynyl)pyridines and propargyl amines was developed, unexpectedly affording a broad range functionalized 1-(2H-pyrrol-3-yl)indolizines in moderate to excellent yields. The developed method is characterized by operational simplicity, ready availability starting materials, high regioselectivity, substrate scope under mild reaction conditions. Ag(I)-promoted cyclization possibly results the formation spiroindolizine, ring-opening rearrangement which may give 1-(2H-pyrrol-3-yl)indolizine. Furthermore, gram-scale synthetic transformations are also studied.

Language: Английский

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