The utilization of light to induce or accelerate a chemical reaction is undoubtedly one of the most promising and sustainable fields in modern organic chemistry. In particular, photoredox catalysis affords facile access to a plethora of transformations that were previously thought to be impossible. These processes rely on a catalyst’s ability to absorb visible light and convert it into chemical energy via single electron transfer to generate the necessitated reactive intermediates. This highly active research field is made up of a diverse community, with research ranging from organometallic and materials chemistry (development of new photocatalysts) to mechanistic and synthetic organic (novel transformations and syntheses) to chemical engineering (improved reactors and processes). This series will be a collection of state-of-the-art research in this continuously growing field, highlighting current progress and provide a perspective for the future of this exciting field.
Potential topics for manuscripts include, but are not limited to:
Graphical Abstract
Scheme 1: Synthesis of g-C3N4 by thermal heating of urea and application to photocatalytic CO2 reduction with...
Figure 1: XRD patterns of g-C3N4 synthesized at different temperatures. A broad peak at around 22 degree, ind...
Figure 2: FTIR spectra of g-C3N4 synthesized at different temperatures. Each spectrum was acquired by a KBr m...
Figure 3: TEM images of g-C3N4 synthesized at different temperatures.
Figure 4: UV–visible diffuse reflectance spectra of g-C3N4 synthesized at different temperatures.
Figure 5: A typical TEM image of Ag-loaded g-C3N4. The synthesis temperature of g-C3N4 was 873 K in this case....
Graphical Abstract
Figure 1: Depiction of the energy levels of a typical organic molecule and the photophysical processes it can...
Figure 2: General catalytic cycle of a photocatalyst in a photoredox organocatalysed reaction. [cat] – photoc...
Figure 3: Structures and names of the most common photocatalysts encountered in the reviewed literature.
Figure 4: General example of a reductive quenching catalytic cycle. [cat] – photocatalyst, [cat]* – photocata...
Figure 5: General example of an oxidative quenching catalytic cycle. [cat] – photocatalyst, [cat]* – photocat...
Scheme 1: Oxidative coupling of aldehydes and amines to amides using acridinium salt photocatalysis.
Figure 6: Biologically active molecules containing a benzamide linkage.
Scheme 2: The photocatalytic reduction of amino acids to produce the corresponding free or protected amines.
Scheme 3: The organocatalysed photoredox base-mediated oxidation of thiols to disulfides.
Scheme 4: C-Terminal modification of peptides and proteins using organophotoredox catalysis.
Scheme 5: The reduction and aryl coupling of aryl halides using a doubly excited photocatalyst (PDI).
Figure 7: Mechanism for the coupling of aryl halides using PDI, which is excited sequentially by two photons.
Scheme 6: The arylation of five-membered heteroarenes using arenediazonium salts under organophotoredox condi...
Scheme 7: The C–H (hetero)arylation of five-membered heterocycles under Eosin Y photocatalysis.
Scheme 8: The C–H sulfurisation of imidazoheterocycles using Eosin B-catalyzed photochemical methods.
Scheme 9: The introduction of the thiocyanate group using Eosin Y photocatalysis.
Scheme 10: Sulfonamidation of pyrroles using oxygen as the terminal oxidant.
Scheme 11: DDQ-catalysed C–H amination of arenes and heteroarenes.
Scheme 12: Photoredox-promoted radical Michael addition reactions of allylic or benzylic carbons.
Figure 8: Proposed mechanistic rationale for the observed chemoselectivities.
Scheme 13: The photocatalytic manipulation of C–H bonds adjacent to amine groups.
Scheme 14: The perylene-catalysed organophotoredox tandem difluoromethylation–acetamidation of styrene-type al...
Figure 9: Examples of biologically active molecules containing highly functionalised five membered heterocycl...
Scheme 15: The [3 + 2]-cycloaddition leading to the formation of pyrroles, through the reaction of 2H-azirines...
Figure 10: Proposed intermediate that determines the regioselectivity of the reaction.
Figure 11: Comparison of possible pathways of reaction and various intermediates involved.
Scheme 16: The acridinium salt-catalysed formation of oxazoles from aldehydes and 2H-azirines.
Scheme 17: The synthesis of oxazolines and thiazolines from amides and thioamides using organocatalysed photor...
Figure 12: Biologically active molecules on the market containing 1,3,4-oxadiazole moieties.
Scheme 18: The synthesis of 1,3,4-oxadiazoles from aldehyde semicarbazones using Eosin Y organophotocatalysis.
Scheme 19: The dimerization of primary thioamides to 1,2,4-thiadiazoles catalysed by the presence of Eosin Y a...
Scheme 20: The radical cycloaddition of o-methylthioarenediazonium salts and substituted alkynes towards the f...
Scheme 21: The dehydrogenative cascade reaction for the synthesis of 5,6-benzofused heterocyclic systems.
Figure 13: Trifluoromethylated version of compounds which have known biological activities.
Scheme 22: Eosin Y-catalysed photoredox formation of 3-substituted benzimidazoles.
Scheme 23: Oxidation of dihydropyrimidines by atmospheric oxygen using photoredox catalysis.
Scheme 24: Photoredox-organocatalysed transformation of 2-substituted phenolic imines to benzoxazoles.
Scheme 25: Visible light-driven oxidative annulation of arylamidines.
Scheme 26: Methylene blue-photocatalysed direct C–H trifluoromethylation of heterocycles.
Scheme 27: Photoredox hydrotrifluoromethylation of terminal alkenes and alkynes.
Scheme 28: Trifluoromethylation and perfluoroalkylation of aromatics and heteroaromatics.
Scheme 29: The cooperative asymmetric and photoredox catalysis towards the functionalisation of α-amino sp3 C–...
Scheme 30: Organophotoredox-catalysed direct C–H amidation of aromatics.
Scheme 31: Direct C–H alkylation of heterocycles using BF3K salts. CFL – compact fluorescent lamp.
Figure 14: The modification of camptothecin, demonstrating the use of the Molander protocol in LSF.
Scheme 32: Direct C–H amination of aromatics using acridinium salts.
Scheme 33: Photoredox-catalysed nucleophilic aromatic substitution of nucleophiles onto methoxybenzene derivat...
Scheme 34: The direct C–H cyanation of aromatics with a focus on its use for LSF.
Graphical Abstract
Figure 1: (a) Molecular structures of the Co4O4 cubane catalysts. (b) Ball-and-stick representation of comple...
Figure 2: UV–vis absorption spectra of 1-R in H2O based on measurements in 10−4 M solution. Inset: scale from...
Figure 3: Correlation of Hammett constants σp for the different ligands with midpoint potentials (E1/2) in co...
Figure 4: Linear sweep voltammetry of 1-R (0.3 mM) or Co(NO3)2·6H2O (1.2 mM); (a) at a 100 mV/s scan rate in ...
Figure 5: The activity of 1-R for (a) water oxidation and (b) CO2 reduction. (c) Long-time course of water ox...
Figure 6: Long-time course of water oxidation for 1-CN and Co2+ under UV–vis light irradiation (λ >300 nm).
Graphical Abstract
Figure 1: a) Light-driven reaction between 2-MBP A and maleimide B for the synthesis of C through a [4 + 2] c...
Figure 2: Generality and limits of the light-driven [4 + 2] cyclization reaction between 2-MBP 1a–g and couma...
Figure 3: Generality and limits of the light-driven [4 + 2] cyclization reaction between 2-MBP 1a–f and chrom...
Scheme 1: MFP parallel setup for higher scale production of 4a (top) and different molecular scaffolds 6a–9a ...
Graphical Abstract
Figure 1: Selected examples of sulfenylated heterocycles used in pharmaceuticals and material chemistry.
Scheme 1: Synthetic routes to organosulfur compounds.
Scheme 2: Aryl sulfide synthesis.
Scheme 3: Substrate scope for arylthiol syntheses. The reaction was performed with 1a–g (0.1 mmol) and 2a–d (...
Figure 2: Crystal structures of compounds 3a, 3d, 3e and 3i.
Scheme 4: Radical trapping experiments.
Figure 3: (a) Changes in the fluorescence spectra (in this case intensity, λEx = 455 nm) of [Ir(dF(CF3)ppy)2(...
Scheme 5: Proposed mechanism for visible light mediated direct C–H sulfenylation.
Figure 4: Black line: UV–vis spectrum of the degassed [Ir] + 1,3,5-TMB mixture (solution A) in ACN. Blue and ...
Graphical Abstract
Scheme 1: Combining double bond isomerization (E/Z) and cyclization/cycloreversion (Z/C) in three-state switc...
Scheme 2: Overview of all sDTE and reference DTE compounds investigated in this study. The compound names ind...
Figure 1: Cyclic voltammograms of sDTE66-Me. a) Both E- (black line) and Z-isomer (blue dashed line) display ...
Figure 2: Spectroelectrochemistry of sDTE66-Me. Absorption changes during CV, insets showing the correspondin...
Scheme 3: Proposed mechanism for the oxidative cyclization of sDTE66-Me. Upon two-fold oxidation, both open i...
Figure 3: Anodic peak potentials (Epa) of sDTEs and reference compounds in MeCN. Solid circles refer to the f...
Figure 4: Cyclic voltammograms of sDTE66-PhCN. The reduction of a) E-sDTE66-PhCN (black line) is reversible, ...
Figure 5: Cyclic voltammogram of DTE-PhFluorene. The ring-closed isomer (red dashed line) is formed both unde...
Figure 6: Cyclic voltammograms of Me2NPh-DTE-PhCN displaying separated one-electron anodic and cathodic waves...
Scheme 4: Proposed mechanism to explain the observed selectivity of anodic and cathodic cyclization in sDTE66...
Graphical Abstract
Figure 1: Typical oxidative and reductive cycle for a photoredox catalyst (PC).
Figure 2: Transitions involved in absorbing species containing π, σ and n electrons.
Figure 3: Ligand to metal charge transfer (illustrated here for a d6 metal complex).
Figure 4: Metal to ligand charge transfer (illustrated here for a d5 metal complex).
Scheme 1: Structures of additives involved in the photoredox catalytic cycles.
Figure 5: Catalytic cycles involved with iodonium salt and (A) (TMS)3SiH, (B) NVK and (C) EDB.
Scheme 2: Structures of photoredox metal-based catalysts.
Scheme 3: Photocatalytical cycle for the Ru complex.
Scheme 4: Structures of photoredox organocatalysts.
Scheme 5: Diversity of the chemical structures of photoredox organocatalysts.
Scheme 6: Structures of benchmarked monomers.
Scheme 7: Structure of the CARET additive.
Scheme 8: Photoredox catalysis mechanism of a visible light-mediated living radical polymerization. (Abbrevia...
Graphical Abstract
Figure 1: Reduction potentials (vs SCE) of common photoredox catalysts, pyrene 16 and phenothiazine 2, in com...
Figure 2: Acceptor or donor-modified phenothiazines 1–11 as potential photoredox catalysts.
Figure 3: Normalized UV–vis absorption spectra above 290 nm of N-phenylphenothiazines 1–11 (left) and represe...
Figure 4: Proposed mechanism for the photoredox-catalyzed addition of methanol to α-methylstyrene (13a). (ET ...