Themed collection 2021 Organic Chemistry Frontiers Review-type Articles
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Macrocyclic and acyclic supramolecular elements for co-precipitation of square-planar gold(III) tetrahalide complexes
Non-covalent interactions control the solid-state packing of AuX4− anions (yellow circles) co-precipitated with different supramolecular elements.
Org. Chem. Front., 2021,8, 1294-1301
https://doi.org/10.1039/D0QO01562H
Three decades of unveiling the complex chemistry of C-nitroso species with computational chemistry
This review revisits the complex reactivity of C-nitroso derivatives through the synergistic combination of computational and synthetic organic chemistry, with an emphasis on the rationalization of mechanisms and selectivities.
Org. Chem. Front., 2022,9, 223-264
https://doi.org/10.1039/D1QO01415C
Recent advances in catalytic enantioselective direct C–H bond functionalization of electron-deficient N-containing heteroarenes
Catalytic enantioselective direct C–H bond functionalization of electron-deficient N-containing heteroarenes represents one of the most straightforward and powerful protocols to construct diverse enantioenriched highly functionalized N-heteroarenes.
Org. Chem. Front., 2022,9, 265-280
https://doi.org/10.1039/D1QO01223A
Recent advances in sustainable organic transformations using methanol: expanding the scope of hydrogen-borrowing catalysis
Recent progress relating to sustainable approaches using methanol as a C1-alkylating agent for C–Me and N–Me bond formation is discussed.
Org. Chem. Front., 2021,8, 7077-7096
https://doi.org/10.1039/D1QO01412A
Metal-hydride hydrogen atom transfer (MHAT) reactions in natural product synthesis
Functionalization of olefins has been an important transformation in synthetic chemistry. This review will focus on the natural product synthesis employing the MHAT reaction as the key strategy.
Org. Chem. Front., 2021,8, 7050-7076
https://doi.org/10.1039/D1QO01139A
1,3-Difunctionalization of alkenes: state-of-the-art and future challenges
This review summarizes the advances in 1,3-difunctionalization of alkenes mediated by Pd-, Ni-, Fe-, and Cu-based catalysts, as well as under metal-free conditions, with an emphasis on the reaction mechanisms and factors governing regioselectivity.
Org. Chem. Front., 2021,8, 7037-7049
https://doi.org/10.1039/D1QO01002F
Recent advances in the direct transformation of propargylic alcohols to allenes
This review summaries a view of the advances in the direct transformation of propargylic alcohols to functionalized allenes.
Org. Chem. Front., 2021,8, 6760-6782
https://doi.org/10.1039/D1QO01151K
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Site-selective modification of peptide backbones
Exciting developments in the site-selective modification of peptide backbones are allowing an outstanding fine-tuning of peptide conformation, folding ability, and physico-chemical and biological properties.
Org. Chem. Front., 2021,8, 6720-6759
https://doi.org/10.1039/D1QO00892G
Achievements in fluorination using variable reagents through a deoxyfluorination reaction
The application of fluorination reagent for the direct conversion of alcohols and phenols to fluorinated analogues.
Org. Chem. Front., 2021,8, 6452-6468
https://doi.org/10.1039/D1QO00952D
Recent advances in cyclization reactions of isatins or thioisatins via C–N or C–S bond cleavage
This review summarizes recent developments on cyclization reactions induced by the C–N or C–S bond cleavage of isatins or thioisatins in the last 5 years, which produce fused products instead of spiro compounds.
Org. Chem. Front., 2021,8, 6433-6451
https://doi.org/10.1039/D1QO00868D
Generation of azolium dienolates as versatile nucleophilic synthons via N-heterocyclic carbene catalysis
The recent advances in N-heterocyclic carbene (NHC)-catalyzed generation of azolium dienolates from different precursors and their synthetic applications for the construction of various valuable molecules are summarized comprehensively in this review.
Org. Chem. Front., 2021,8, 6138-6166
https://doi.org/10.1039/D1QO01127H
Advances in regioselective functionalization of 9-phenanthrenols
Various approaches are discussed for regioselective functionalization and transformation of 9-phenanthrenol and its ether derivatives, which are readily available from phenanthrene in coal tar.
Org. Chem. Front., 2021,8, 6125-6137
https://doi.org/10.1039/D1QO00811K
Visible light mediated functionalization of allenes
This review summarizes the visible light mediated strategies for the functionalization of allenes.
Org. Chem. Front., 2021,8, 5651-5667
https://doi.org/10.1039/D1QO00955A
Synthesis of diverse heterocyclic frameworks using cyclopentadienones via the Diels–Alder strategy
In this review article, we briefly summarize the versatility of Diels–Alder reactions of cyclopentadienones and concise routes to diverse hetero-atom bearing PAHs using cyclones as building blocks.
Org. Chem. Front., 2021,8, 5608-5650
https://doi.org/10.1039/D1QO00784J
The Ugi three-component reaction and its variants
A broad variety of α-aminoamide-based compounds have been synthesized via the three-component version of the Ugi reaction (U-3CR) or by any of its variants (Ugi-Zhu-3CR, Orru-3CR, Ugi-4C-3CR, Ugi-Joullié-3CR, GBB-3CR, Ugi-Reissert-3CR, and so on).
Org. Chem. Front., 2021,8, 5460-5515
https://doi.org/10.1039/D1QO00313E
Synthetic applications of α,α-difluoroarylacetic acids and salts via decarboxylative functionalization
α,α-Difluoroarylacetic acids are stable, inexpensive and readily available building blocks which can be used to access various difluoromethylated aryl motifs via decarboxylative functionalization for the formation of carbon–carbon and carbon-heteroatom (F, O, S) bonds.
Org. Chem. Front., 2021,8, 5516-5530
https://doi.org/10.1039/D1QO00775K
Recent advances for the synthesis of chiral sulfones with the sulfone moiety directly connected to the chiral center
The recent development of strategies for the asymmetric synthesis of chiral sulfones with sulfone moieties directly connected to the stereocenters.
Org. Chem. Front., 2021,8, 5574-5589
https://doi.org/10.1039/D1QO00663K
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Direct synthetic routes to functionalised crown ethers
Modification of crown ethers via grafting of functional groups represents a convenient yet underexplored tool.
Org. Chem. Front., 2021,8, 5531-5549
https://doi.org/10.1039/D1QO00699A
Recent progress in the total synthesis of pyrrole-containing natural products (2011–2020)
This review discusses total syntheses of pyrrole-containing natural products over the last ten years, highlighting recent advances in the chemistry of pyrroles in the context of their innate reactivity, and their preparation in complex settings.
Org. Chem. Front., 2021,8, 5550-5573
https://doi.org/10.1039/D0QO01574A
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Emerging computational approaches for the study of regio- and stereoselectivity in organic synthesis
Computational chemistry has become important in organic synthesis as it provides a detailed understanding of molecular structures and properties and detailed reaction mechanisms.
Org. Chem. Front., 2021,8, 5165-5181
https://doi.org/10.1039/D1QO00531F
Recent developments in the difunctionalization of alkenes with C–N bond formation
Various alkene difunctionalization reactions involving nitridization, diamination, azidation, oxyamination, carboamination, aminohalogenation, and nitration are introduced in this review.
Org. Chem. Front., 2021,8, 5206-5228
https://doi.org/10.1039/D1QO00375E
1,2,4,5-Tetrazine derivatives as components and precursors of photo- and electroactive materials
Synthetic approaches to 3,6-disubstituted-1,2,4,5-tetrazine systems are analyzed, and their properties attractive to practical applications in photo- and electroactive materials are overviewed.
Org. Chem. Front., 2021,8, 5182-5205
https://doi.org/10.1039/D1QO00465D
SOMOphilic alkynylation using acetylenic sulfones as functional reagents
Recent advancements in SOMOphilic alkynylation reactions by using acetylenic sulfones as functional reagents are summarized.
Org. Chem. Front., 2021,8, 5145-5164
https://doi.org/10.1039/D1QO00798J
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Green strategies for transition metal-catalyzed C–H activation in molecular syntheses
Sustainable strategies for the activation of inert C–H bonds towards improved resource-economy.
Org. Chem. Front., 2021,8, 4886-4913
https://doi.org/10.1039/D1QO00727K
Remote C(sp3)–H functionalization via catalytic cyclometallation: beyond five-membered ring metallacycle intermediates
Despite impressive recent momentum gained in C(sp3)–H activation, achieving high regioselectivity in molecules containing different C–H bonds with similar high energy without abusing tailored substitution remains as one of the biggest challenges.
Org. Chem. Front., 2021,8, 4914-4946
https://doi.org/10.1039/D1QO00389E
Hybrid phosphorus–viologen dendrimers as new soft nanoparticles: design and properties
Design of new families of dendritic soft nanoparticles constituted of phosphorus, viologen and carbosilane fragments and their properties as nanomaterials and applications in biology.
Org. Chem. Front., 2021,8, 4607-4622
https://doi.org/10.1039/D1QO00511A
Keep glowing and going: recent progress in diketopyrrolopyrrole synthesis towards organic optoelectronic materials
Recent progress in the syntheses of DPP derivatives is summarized as well as the structure–property relationships of the derivatives, including the syntheses of DPP cores, N-functionalization reactions, and π-extensions on and along the DPP cores.
Org. Chem. Front., 2021,8, 4560-4581
https://doi.org/10.1039/D1QO00613D
Recent advances of Ritter reaction and its synthetic applications
This review provides a comprehensive survey of Ritter reactions from 2014 to 2020.
Org. Chem. Front., 2021,8, 4623-4664
https://doi.org/10.1039/D1QO00496D
Recent advances in the functionalization of saturated cyclic amines
Functionalized cyclic amines are the essential structural moieties of numerous biologically active compounds. This review summarized the most recent advances in the C–H, C–N and C–C bond functionalization of saturated cyclic amines.
Org. Chem. Front., 2021,8, 4582-4606
https://doi.org/10.1039/D1QO00171J
Recent advances in multi-component reactions and their mechanistic insights: a triennium review
This review summarizes the recent developments in MCRs, incorporating different strategies along with their mechanistic aspects.
Org. Chem. Front., 2021,8, 4237-4287
https://doi.org/10.1039/D0QO01480J
Recent advances in organocatalytic asymmetric multicomponent cascade reactions for enantioselective synthesis of spirooxindoles
Catalytic asymmetric MCCRs for enantioselective synthesis of spirooxindoles by using chiral phosphoric acids, amines, bifunctional thiourea/squaramides and metal-based reagents as catalysts.
Org. Chem. Front., 2021,8, 4315-4348
https://doi.org/10.1039/D1QO00220A
Recent advances in the application of tetrabromomethane in organic synthesis
This review article covers the use of tetrabromomethane as mediator, catalyst and reagents for organic synthesis for the period from 2007 to 2020.
Org. Chem. Front., 2021,8, 4288-4314
https://doi.org/10.1039/D0QO01369B
Covalent organic framework-based membranes for liquid separation
This review summarizes the synthesis and characterization methods of COF-based membranes in recent years and discusses their separation mechanism and application in liquid separation.
Org. Chem. Front., 2021,8, 3943-3967
https://doi.org/10.1039/D0QO01354D
Structure determination, correction, and disproof of marine macrolide natural products by chemical synthesis
Integration of chemical synthesis, NMR spectroscopy, and various analytical means is key to success in the structure elucidation of stereochemically complex marine macrolide natural products.
Org. Chem. Front., 2021,8, 3990-4023
https://doi.org/10.1039/D1QO00481F
Recent advances in transition metal-catalyzed reactions of carbamoyl chlorides
This review highlights the recent advancements of carbamoyl chlorides in transition metal-catalyzed reactions to access various amide-containing molecules and heterocycles.
Org. Chem. Front., 2021,8, 4024-4045
https://doi.org/10.1039/D0QO01648A
Recent advances of chromone-based reactants in the catalytic asymmetric domino annulation reaction
Chiral polycyclic chromanones are important heterocyclic frameworks that constitute the core structures of many natural products and bioactive molecules.
Org. Chem. Front., 2021,8, 3968-3989
https://doi.org/10.1039/D1QO00269D
Recent advance in the C–F bond functionalization of trifluoromethyl-containing compounds
The C–F bond is the strongest single bond in organic compounds.
Org. Chem. Front., 2021,8, 3915-3942
https://doi.org/10.1039/D1QO00037C
C–H hetero-functionalization of arenes through palladacyclopentane-type intermediates
In this review article, we summarized recent advances in C–H hetero-functionalization of arenes through palladacyclopentane-type intermediates.
Org. Chem. Front., 2021,8, 3883-3914
https://doi.org/10.1039/D0QO01350A
Strategies and methodologies for the construction of spiro-γ-lactams: an update
This review gives an insight into the most recent synthetic methodologies towards spiro-γ-lactams, a class of compounds that are present in a wide range of synthetic bioactive and naturally occurring molecules.
Org. Chem. Front., 2021,8, 3543-3593
https://doi.org/10.1039/D0QO01564D
Photo-induced transition-metal and external photosensitizer-free organic reactions
Photoreactions have become powerful synthetic tools with a broad scope of applications. This review mainly focuses on photoreactions in the absence of transition-metals and photosensitizers, and highlights the mechanisms of such reactions.
Org. Chem. Front., 2021,8, 3594-3613
https://doi.org/10.1039/D1QO00359C
Recent advances in annulation reactions based on zwitterionic π-allyl palladium and propargyl palladium complexes
Carbocyclic and heterocyclic compounds could be constructed through the palladium-catalyzed annulation reactions of zwitterionic π-allyl palladium or propargyl palladium complexes with unsaturated electrophiles.
Org. Chem. Front., 2021,8, 3475-3501
https://doi.org/10.1039/D1QO00273B
C(sp3)–H functionalization with isocyanides
This review highlights the state-of-the-art advances in C(sp3)–H functionalization involving isocyanides through the synergistic combination of isocyanide insertion and C(sp3)–H bond activation.
Org. Chem. Front., 2021,8, 3525-3542
https://doi.org/10.1039/D1QO00153A
Recent advances in NHC–palladium catalysis for alkyne chemistry: versatile synthesis and applications
This review summarizes the recent developments in NHC–palladium catalysis for alkyne chemistry: versatile synthesis and applications.
Org. Chem. Front., 2021,8, 3502-3524
https://doi.org/10.1039/D1QO00111F
Sequential activation of thioglycosides enables one-pot glycosylation
This review describes recent developments in relative reactivity value (RRV) controlled sequential glycosylation, pre-activation based iterative glycosylation, and sulfoxide activation initiated one-pot glycosylation.
Org. Chem. Front., 2021,8, 3150-3165
https://doi.org/10.1039/D0QO01414A
Cyanation: a photochemical approach and applications in organic synthesis
This review summarises the photocatalytic cyanation strategies to construct C(sp2)–CN, C(sp3)–CN and X–CN (X = N, S) bonds.
Org. Chem. Front., 2021,8, 3166-3200
https://doi.org/10.1039/D1QO00162K
The ammoxidation of alcohols over heterogeneous catalysts for the green synthesis of nitriles
This is the first review on the ammoxidation of alcohols over heterogeneous catalysts, in which issues and potential solutions are demonstrated.
Org. Chem. Front., 2021,8, 3137-3149
https://doi.org/10.1039/D1QO00275A
Recent advances in electrochemically driven radical fluorination and fluoroalkylation
Electrochemical fluorination (ECF) refers to the introduction of fluorine-containing moieties into organic molecules under electrochemical conditions.
Org. Chem. Front., 2021,8, 2786-2798
https://doi.org/10.1039/D1QO00054C
Stereoselective synthetic strategies of stereogenic carbon centers featuring a difluoromethyl group
The scope of this review is to summarize routine asymmetric synthetic methods which enable the effective and selective introduction of difluoromethyl groups into the desired compounds, providing a general introduction to this important research area.
Org. Chem. Front., 2021,8, 2799-2819
https://doi.org/10.1039/D1QO00032B
Recent progress on the construction of axial chirality through transition-metal-catalyzed benzannulation
Useful chiral biaryls have been constructed through rhodium and gold complex-catalyzed asymmetric benzannulation strategies.
Org. Chem. Front., 2021,8, 2772-2785
https://doi.org/10.1039/D1QO00307K
Benzannulation strategies for the synthesis of carbazoles, indolocarbazoles, benzocarbazoles, and carbolines
This review presents a critical and authoritative analysis of several exciting benzannulation approaches developed in the past decade for the construction of carbazoles, indolocarbazoles, benzocarbazoles, and carbolines.
Org. Chem. Front., 2021,8, 2710-2771
https://doi.org/10.1039/D1QO00092F
Recent advances in the synthesis and reactivity of quinoxaline
Quinoxalines are observed in several bioactive molecules and have been widely employed in designing molecules for DSSC's, optoelectronics, and sensing applications. Therefore, developing newer synthetic routes as well as novel ways for their functionalization is apparent.
Org. Chem. Front., 2021,8, 2820-2862
https://doi.org/10.1039/D0QO01575J
Advances in organocatalytic asymmetric reactions of vinylindoles: powerful access to enantioenriched indole derivatives
This review summarizes advances in vinylindole-based organocatalytic asymmetric reactions since 2008 and includes the applications of some methodologies in the total synthesis of natural products, points out remaining challenges in this research area.
Org. Chem. Front., 2021,8, 2643-2672
https://doi.org/10.1039/D0QO01643H
Recent advances in sustainable synthesis of N-heterocycles following acceptorless dehydrogenative coupling protocol using alcohols
In this review, we have summarized various aspects of homogeneous and heterogeneously catalyzed recent advancements in the synthesis of heterocycles following the ADC approach.
Org. Chem. Front., 2021,8, 2673-2709
https://doi.org/10.1039/D0QO01577F
Recent progress in the synthesis of the furanosteroid family of natural products
This review focuses on an overview of recent advances in the synthesis of furanosteroids and illustrates their applications in medicinal chemistry over the period of 2005–present.
Org. Chem. Front., 2021,8, 2608-2642
https://doi.org/10.1039/D0QO01454K
Catalytic asymmetric synthesis of monofluoroalkenes and gem-difluoroalkenes: advances and perspectives
The latest achievements in the catalytic asymmetric synthesis of both monofluoro- and gem-difluoroalkenes are discussed.
Org. Chem. Front., 2021,8, 2315-2327
https://doi.org/10.1039/D0QO01630F
Recent advances on transition-metal-catalysed asymmetric reductive amination
This review focuses on the recent progress of homogeneous transition-metal-catalysed asymmetric reductive amination of ketones with diverse nitrogen sources.
Org. Chem. Front., 2021,8, 2328-2342
https://doi.org/10.1039/D1QO00300C
Organocatalytic dimensions to the C–H functionalization of the carbocyclic core in indoles: a review update
A review highlighting important research findings in remote C–H activation processes using effectual organocatalytic perspectives. The challenging indole carbocyclic ring positions were successfully accessed with proper regio- and stereocontrols.
Org. Chem. Front., 2021,8, 2343-2365
https://doi.org/10.1039/D0QO01466D
Synthesis of enantioenriched α-heteroatom functionalised aldehydes by chiral organocatalysis and their synthetic applications
Asymmetric organocatalysis is a versatile method for the enantioselective α-functionalisation of aldehydes. The synthetic scope for chiral α-heteroatom substituted aldehydes is examined including their applications in synthesis.
Org. Chem. Front., 2021,8, 2287-2314
https://doi.org/10.1039/D1QO00101A
Fluorination and fluoroalkylation of alkenes/alkynes to construct fluoro-containing heterocycles
This review summarize the established strategies through fluorination and fluoroalkylation of alkenes/alkynes for constructing fluoro-containing heterocycles. Reaction scopes, mechanisms and some shortcomings are also discussed.
Org. Chem. Front., 2021,8, 2079-2109
https://doi.org/10.1039/D0QO01629B
Structural characterisation of natural products by means of quantum chemical calculations of NMR parameters: new insights
In this review, we focus in all aspects of NMR simulation of natural products, from the fundamentals to the new computational toolboxes available, combining advanced quantum chemical calculations with upstream data processing and machine learning.
Org. Chem. Front., 2021,8, 2019-2058
https://doi.org/10.1039/D1QO00034A
Recent advances in the synthesis of indole embedded heterocycles with 3-diazoindolin-2-imines
The preparations, reactivity and synthetic applications of 3-diazoindolin-2-imines, a valuable class of α-diazo amidines, are reviewed.
Org. Chem. Front., 2021,8, 2059-2078
https://doi.org/10.1039/D0QO01515F
Strategies for the synthesis of furo-pyranones and their application in the total synthesis of related natural products
The furo-pyranone framework is widely present in the molecular structure of various biologically potent natural products and un-natural small molecules, and it represents a valuable target in synthetic organic chemistry and medicinal chemistry.
Org. Chem. Front., 2021,8, 2110-2162
https://doi.org/10.1039/D0QO01421D
Recent advances in quinazolinones as an emerging molecular platform for luminescent materials and bioimaging
This review summarized recent advances relating to the luminescence properties of quinazolinones and their applications in fluorescent probes, biological imaging and luminescent materials. Their future outlook is also included.
Org. Chem. Front., 2021,8, 1867-1889
https://doi.org/10.1039/D0QO01425G
Photoexcited molecular probes for selective and revertible imaging of cellular reactive oxygen species
Redox homeostasis is key to maintaining the normal physiological status of living cells.
Org. Chem. Front., 2021,8, 1302-1314
https://doi.org/10.1039/D0QO01260B
The oxa-Michael reaction in the synthesis of 5- and 6-membered oxygen-containing heterocycles
In this review, we provide an updated account on the recent advances and applications of oxa-Michael reaction in the synthesis 5- and 6-membered monocyclic oxygen-containing heterocyclic compounds published in the literature since 2013 to date.
Org. Chem. Front., 2021,8, 1329-1344
https://doi.org/10.1039/D0QO01312A
Recent advances in cascade radical cyclization of radical acceptors for the synthesis of carbo- and heterocycles
This review is devoted to highlighting main achievements in the development of cascade radical cyclization of radical acceptors for the synthesis of carbo- and heterocycles.
Org. Chem. Front., 2021,8, 1345-1363
https://doi.org/10.1039/D0QO01453B
Recent advances in hydride transfer-involved C(sp3)–H activation reactions
This review summarizes the recent progresses (2016–2020) in the hydride transfer-enabled C(sp3)–H activation according to the reaction types, categorized into the intramolecular/intermolecular C(sp3)–H functionalization, and hydride reduction.
Org. Chem. Front., 2021,8, 1364-1383
https://doi.org/10.1039/D0QO01502D
An electrochemical perspective on the roles of ligands in the merger of transition-metal catalysis and electrochemistry
A perspective on the roles of ligands in transition-metal catalysis under electrochemical conditions is provided.
Org. Chem. Front., 2021,8, 1315-1328
https://doi.org/10.1039/D0QO01227K
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Stereoselective synthesis and applications of spirocyclic oxindoles
This review summaries recent synthetic developments towards spirocyclic oxindoles and applications as valuable medicinal and synthetic targets.
Org. Chem. Front., 2021,8, 1026-1084
https://doi.org/10.1039/D0QO01085E
Recent advances in transition metal-catalyzed olefinic C–H functionalization
Recent advances during 2015–2020 in the field of metal-catalyzed olefinic C–H functionalization are organized according to the metal center of the catalyst, with an emphasis on the similarities and differences among different catalysts.
Org. Chem. Front., 2021,8, 1085-1101
https://doi.org/10.1039/D0QO01159B
About this collection
Critical reviews and highlight articles published in Organic Chemistry Frontiers during 2021 are collated as below for the benefit of readers.