Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

• Stephanie G. E. Amos,
• Marion Garreau,
• Luca Buzzetti and
• Jerome Waser

Beilstein J. Org. Chem. 2020, 16, 1163–1187, doi:10.3762/bjoc.16.103

• cations and radical anions) Recently, the exploitation of alkenyl and aryl radical ions has emerged as a platform for the functionalization of small molecules. They appear as attractive intermediates for a direct alkene difunctionalization or arene C–H functionalization. In particular, radical cations are

• direct activation of the ß-C–H bond [109]. However, organic dyes have not yet been broadly applied for such transformations. Charged aryl radical species Arene radical cations are valuable intermediates that enable the direct C–H functionalization of the aromatic species. They can be accessed through the

• -Acr+ scaffold. In 2015, they developed a site-selective C–H amination of arenes (Scheme 25) [110]. The arenes 25.1 could be aminated by various N-heterocycles 25.2 for the synthesis of the C–H functionalization products 25.3 with fine-tuned Mes-di(t-Bu)Acr+ (OD4) as a photocatalyst. In this

A simple and easy to perform synthetic route to functionalized thienyl bicyclo[3.2.1]octadienes

• Dragana Vuk,
• Irena Škorić,
• Valentina Milašinović,
• Krešimir Molčanov and
• Željko Marinić

Beilstein J. Org. Chem. 2020, 16, 1092–1099, doi:10.3762/bjoc.16.96

• methodology [8][9][10][11][12][13][14][15][16][17][18][19][20][21]. By using a simple photochemical procedure, it was possible to obtain a whole library of novel bicyclo[3.2.1]octadiene derivatives, available for further functionalization, which could enable the easier investigation of the relationship

• of two aromatic units (Scheme 1). The idea herein was to prepare thienyl analogues of the annulated furyl derivatives, as substrates suitable for biological testing and/or new precursors for further functionalization. Results and Discussion As starting precursors two bicyclic thiophene derivatives 1

• functionalization. These functionalizations, beside the addition reaction, could involve photooxygenation reactions (Scheme 5) [1][22][23][24][25], previously studied in our laboratory. These reactions could result in a completely new spectrum of products, with preserved bicyclo[3.2.1.]octadiene skeleton, crucial

Palladium-catalyzed regio- and stereoselective synthesis of aryl and 3-indolyl-substituted 4-methylene-3,4-dihydroisoquinolin-1(2H)-ones

• Valeria Nori,
• Antonio Arcadi,
• Armando Carlone,
• Fabio Marinelli and
• Marco Chiarini

Beilstein J. Org. Chem. 2020, 16, 1084–1091, doi:10.3762/bjoc.16.95

• antimetastatic agents [14]. Fittingly, the development of efficient strategies for their construction and peripheral functionalization represents still an active research area aimed to achieve structural diversity [15][16][17][18]. Carbometalations of alkynes constitute a powerful tool for the regio- and

Copper-based fluorinated reagents for the synthesis of CF₂R-containing molecules (R ≠ F)

• Louise Ruyet and
• Tatiana Besset

Beilstein J. Org. Chem. 2020, 16, 1051–1065, doi:10.3762/bjoc.16.92

• functionalization of alkyl bromides, alkyl mesylates, aryldiazonium salts [43] as well as electron-rich arenes [44] (Scheme 4). In 2015, the group of Qing investigated the oxidative difluoromethylation reaction of terminal alkynes with TMSCF2H via a copper-mediated reaction [45]. Using a stoichiometric amount of

• CuI, in the presence of t-BuOK and 9,10-phenanthraquinone, the functionalization of a panel of (hetero)aromatic and aliphatic terminal alkynes was achieved (Scheme 5). A good functional group tolerance was observed as alkynes bearing a cyano, ester, bromo or amino group among others were suitable

• -generated copper-based reagent (19 examples, up to 80% yield, Scheme 7e). With a similar method and in the presence of 1,10-phenanthroline as a ligand, the functionalization of alkenyl halides (8 examples, up to 82% yield), allyl halides (7 examples, up to 99% yield) and benzyl bromides (6 examples, up to

Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches

• Rodrigo Costa e Silva,
• Luely Oliveira da Silva,
• Aloisio de Andrade Bartolomeu,
• Timothy John Brocksom and
• Kleber Thiago de Oliveira

Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83

• detoxification of anthropogenic chemicals (cytochrome P450) and oxygen transport (hemoglobin) [5][6]. Taking into account this big group of molecules, porphyrins are notable due to both their physicochemical and electronic properties, which can be fine-tuned by functionalization of the core structures [8]. The

• products were obtained with good TON (up to 880) and high selectivity (91–99.5%), even though the aryl C–F bonds present a high bond dissociation energy (BDE) (Scheme 13). Using a similar photocatalytic system, 2-methyl-2,3-dihydrobenzofuran was produced by an intramolecular hydro-functionalization of

• ]. Che and co-workers showed that a variety of nucleophiles can be used for the α-functionalization of N-aryltetrahydroisoquinolines using a low Pd-TPFPP loading. This photocatalyst provided the α-aminonitriles in 71–85%, β-nitroamines in 72–83%, β-diester amines in 68–74%, and α-amino phosphonates in 63

Diversity-oriented synthesis of 17-spirosteroids

• Benjamin Laroche,
• Thomas Bouvarel,
• Martin Louis-Sylvestre and
• Bastien Nay

Beilstein J. Org. Chem. 2020, 16, 880–887, doi:10.3762/bjoc.16.79

• relevant compounds [15][16][17]. Once a biologically relevant scaffold has been identified, the diversity-generating workflow can basically follow two complementary approaches, either by de novo synthesis sequentially incorporating the diversity [15][18][19], or by late functionalization of easily

• accessible biologically relevant materials. This second strategy can take benefit of existing functional groups on the substrate, or rely on direct C–H functionalization [20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Taking steroids as an example of highly targeted privileged structures, numerous

• H-12 (the dotted line indicates a weak correlation); (b) Model to explain the diene–dienophile interaction during the Diels–Alder reaction. Two diversity-oriented strategies: (a) Diversity installed during the construction of the skeleton; (b) Diversity installed lately by functionalization

Copper catalysis with redox-active ligands

• Agnideep Das,
• Yufeng Ren,
• Cheriehan Hessin and
• Marine Desage-El Murr

Beilstein J. Org. Chem. 2020, 16, 858–870, doi:10.3762/bjoc.16.77

• ], and perform C–H functionalization through aerobic dearomatization of phenols [35]. These broad synthetic outcomes further led to a unified approach for the preparation of 1,2-oxy-aminoarenes by phenol–amine couplings (Scheme 10) [36]. We reported the formation of a C–N bond through copper-catalyzed

• oxidation of alcohols and representative substrate scope. Introduction of H-bonding network in the ligand coordination sphere. Well-defined isatin copper complexes. Catalyst control in the biomimetic phenol ortho-oxidation. Structural diversity accessible by direct functionalization. Copper-catalyzed

Aldehydes as powerful initiators for photochemical transformations

• Maria A. Theodoropoulou,
• Nikolaos F. Nikitas and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

• desired products 140n–t in moderate to good yields (Scheme 30). A few months later, the same research group extended this methodology to an α-C(sp3)–H bond functionalization of nitrogen-containing molecules and thioethers [58]. In order to achieve the highest yield, an optimum concentration of acetone (4

• proposed mechanism for the C(sp3)–H functionalization of N-containing molecules and thioethers is in accordance with the one described previously for ether functionalizations and is presented in Scheme 35. In 2019, Kokotos and co-workers employed 4-cyanobenzaldehyde (53) as the photoinitiator for the

• the photoredox merger reaction. Proposed mechanism for the C(sp3)–H alkylation/arylation of ethers. Substrate scope for the photochemical alkylation of ethers. C(sp3)–H Functionalization of N-containing molecules. Substrate scope for the photochemical alkylation of N-containing molecules. Additional

Preparation of 2-phospholene oxides by the isomerization of 3-phospholene oxides

• Péter Bagi,
• Réka Herbay,
• Nikolett Péczka,
• Zoltán Mucsi,
• István Timári and
• György Keglevich

Beilstein J. Org. Chem. 2020, 16, 818–832, doi:10.3762/bjoc.16.75

• antitumor [27][28][29][30], antifungal [31][32] or GABA receptor antagonist activity [33]. The most common synthesis of a given functionalized P-heterocyclic compound comprises the synthesis of the heterocyclic core, followed by its functionalization [27][29][34][35]. This latter step is of special

• importance for biologically active compounds, as specific functional groups are necessary to have a desired biological activity. Considering the functionalization of the five-membered P-heterocycles, the derivatives containing double bond(s) (i.e., phospholenes or phospholes) are of special importance, as a

• . General strategies for the preparation and functionalization of 2- and 3-phospholene oxides. The full time experimental kinetic curves (a); The initial part of the kinetic curves of 1c–f and 1h (b); Initial and second fittings on the kinetic curve of 1c (c). For more kinetic curves, see Supporting

Photocatalytic deaminative benzylation and alkylation of tetrahydroisoquinolines with N-alkylpyrydinium salts

• David Schönbauer,
• Carlo Sambiagio,
• Timothy Noël and
• Michael Schnürch

Beilstein J. Org. Chem. 2020, 16, 809–817, doi:10.3762/bjoc.16.74

• alkyl and allyl groups were also successfully introduced via the same method. Additionally, the typically applied N-phenyl group in the THIQ substrate could be replaced by the cleavable p-methoxyphenyl (PMP) group and successful N-deprotection was demonstrated. Keywords: C–H functionalization; C(sp3)–C

• (sp3) coupling; deaminative coupling; Katritzky salt; photoredox catalysis; Introduction The selective formation of new carbon–carbon bonds via direct C–H functionalization bears the potential of being a process of high efficiency [1][2][3]. Since C–H bonds are omnipresent in organic compounds it is

• steps for the installation and removal of the directing group. However, there is also a good number of substrates containing C–H bonds that are inherently more reactive than others in the same molecule, and in such cases a selective C–H functionalization can be achieved in the absence of any directing

Reaction of indoles with aromatic fluoromethyl ketones: an efficient synthesis of trifluoromethyl(indolyl)phenylmethanols using K₂CO₃/n-Bu₄PBr in water

• Thanigaimalai Pillaiyar,
• Masoud Sedaghati and
• Gregor Schnakenburg

Beilstein J. Org. Chem. 2020, 16, 778–790, doi:10.3762/bjoc.16.71

• advantages of this protocol. Keywords: C–C-bond formation; C3-funtionalization of indole; diindolylmethane; Friedel–Crafts reaction; indole; indole-3-carbinol; large-scale synthesis; recyclability; Introduction (1H-Indol-3-yl)methanols have emerged as versatile pre-electrophiles for C–C functionalization

• cycle. 3-Indolylmethanols are versatile pre-electrophiles for C–C functionalization at the 3-position of indoles. Particularly, the Friedel–Crafts alkylation of 3-indolylmethanols with indoles has become a useful method for the preparation of 3,3'-, and 3,6'-DIMs, which are known to possess a wide

• protocol for the preparation of trifluoromethyl(indolyl)phenylmethanols, which are of significant interest serving as pre-electrophiles for C–C functionalization at the 3-position of indoles. Particularly, the Friedel–Crafts alkylation of 3-indolylmethanols with indoles has become a useful method for the

Towards triptycene functionalization and triptycene-linked porphyrin arrays

• Gemma M. Locke,
• Keith J. Flanagan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2020, 16, 763–777, doi:10.3762/bjoc.16.70

• directly to the periphery of triptycene or via various linkers; arrays with six chromophores 3 have thus far eluded us [26][27]. While much work has been done on the functionalization of the aromatic rings of triptycene as in 2 or 3 [24][25][26][27][28][29][30], the attachment of chromophores at the

• bridgehead positions has yet to be realized. Functionalization of the bridgehead positions of triptycene (as in 4) allows for the attachment of moieties in a 180° linear fashion, subsequently accessing the molecular rotation observed in several other linearly substituted triptycenes [31]. Attaching

• [34] directly through various Pd-catalyzed or organocopper cross-coupling [35] reactions. However, exploratory studies did not show much promise and this approach was abandoned, as was the functionalization of 9,10-dibromoanthracene with phenyl spacers prior to triptycene formation (see Supporting

Combining enyne metathesis with long-established organic transformations: a powerful strategy for the sustainable synthesis of bioactive molecules

• Valerian Dragutan,
• Ileana Dragutan,
• Albert Demonceau and
• Lionel Delaude

Beilstein J. Org. Chem. 2020, 16, 738–755, doi:10.3762/bjoc.16.68

• obtained by Lee who carried out an intermolecular enyne metathesis between an alkynyl boronate and an olefinic substrate in the presence of the Grubbs 2nd generation catalyst [71]. The reaction was highly stereoselective and favored the formation of the desired E-isomer (E/Z = 7.5:1). The functionalization

• subunit, including Diels–Alder cycloaddition and advanced functionalization reactions, gave access to manzamine A and E. Rhodexin A Jung et al. [87][88][89] succeeded in the stereoselective synthesis of rhodexin A (17), a steroid with potent cardiotonic properties and with activity against human leukemia

• efficiently produce key 1,3-dienic frameworks, further subjected to sequential functionalization. The main focus was placed on strategies combining enyne metathesis with traditional chemical transformations such as Diels–Alder cycloaddition, Suzuki–Miyaura or Heck cross-couplings, aromatization, epoxidation

Recent advances in Cu-catalyzed C(sp³)–Si and C(sp³)–B bond formation

• Balaram S. Takale,
• Ruchita R. Thakore,
• Elham Etemadi-Davan and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

• reactions are discussed. Keywords: C–B bonds; copper catalysis; C–Si bonds; enantioselective reactions; sp3 carbon functionalization; Introduction Transition-metal-catalyzed silylation and borylation are useful transformations [1], widely studied because organosilicon [2][3] and organoboron compounds [4

• equivalent to dienones (Scheme 29). In this case, however, instead of forming an enol, a highly stable phenol resulted from the addition of silicon at the methide position. The reaction was exclusively done on electron-rich systems 163–166. Nonetheless, further functionalization of one of the silicon

• )-(DTBM)-Segphos as the active catalyst in THF for the formation of chiral, nonracemic α-alkoxyorganoboronate esters (up to 99% ee; 454–457). MeOH was used as the proton source. Further functionalization can be considered as an umpolung pathway for the formation of enantioenriched tertiary alcohols

Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties

• Takahide Shimada,
• Shigeki Mori,
• Masatoshi Ishida and
• Hiroyuki Furuta

Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53

• -materials. Keywords: alkynylation; BODIPY; direct C–H functionalization; gold(I); Introduction Boron-dipyrromethene (BODIPY, 1) and its derivatives are representative families of fluorophores that have been widely used in applications for bioimaging [1][2][3][4][5][6], photodynamic therapy [7][8][9][10

• the synthesis of ethynyl-substituted BODIPY derivatives 3–6 by gold(I)-catalyzed direct C–H functionalization (Figure 1c). By taking advantage of the reactivity of β-(2 and 6)-positions of BODIPY (1), which are susceptible to electrophilic reactions, β,β'-diethynyl-substituted BODIPYs 5 and 6 were

• nature of BODIPY, the reactivity of the 2,6-positions is intrinsically low toward electrophiles, which hampers the β-selective functionalization. We, therefore, tested the corresponding reaction using tetramethyl-substituted BODIPY 1b that is expected to have an enhanced electron density of the BODIPY

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• article, we have provided an overview on the synthesis and functionalization of SiO2 nanoparticles and on the investigation on their catalytic applications in CuAAC reactions. Rhee et al. immobilized Cu(I) and Cu(II) species onto reverse-phased silica gel [25]. In this work, a 2-pyridinecarboxaldehyde

• provide an overview on the synthesis and functionalization of carbon nanomaterials the catalytic application of these materials in CuAAC reactions. Very recently, CuCl2 on fabricated graphitic polymeric C3N4-supported CuCl2 (Cu@g-C3N4, 74) was prepared as an off-white bluish solid in two simple steps [76

• ]. Because of the mentioned reasons, as well as due to the low toxicity and the magnetically reusability of these nanoparticles, they were also used in organic reactions. As such, in this review, we provide an overview on the synthesis and functionalization of MNPs and on investigations on their catalytic

Copper-catalyzed remote C–H arylation of polycyclic aromatic hydrocarbons (PAHs)

• Anping Luo,
• Min Zhang,
• Zhangyi Fu,
• Jingbo Lan,
• Di Wu and
• Jingsong You

Beilstein J. Org. Chem. 2020, 16, 530–536, doi:10.3762/bjoc.16.49

• a challenging task due to the inaccessibility of the corresponding 7-halonaphthalene substrates [12]. Recently, transition metal-catalyzed C–H bond functionalization has emerged as a powerful tool to construct various biaryl skeletons [13][14][15][16][17]. The direct C7−H arylation of 1-naphthoic

• of our ongoing research on direct C–H bond functionalization [20][27][28][29], we herein represent a copper-catalyzed remote C–H arylation of PAHs with aryliodonium salts as arylating reagents (Scheme 1). This protocol is compatible with different PAH substrates including 1-naphthamides, phenanthrene

Synthesis of triphenylene-fused phosphole oxides via C–H functionalizations

• Md. Shafiqur Rahman and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2020, 16, 524–529, doi:10.3762/bjoc.16.48

• through two distinct C–H functionalization reactions as key steps. The phosphole ring was constructed by a three-component coupling of 3-(methoxymethoxy)phenylzinc chloride, an alkyne, and dichlorophenylphosphine, involving the regioselective C–H activation of the C2 position of the arylzinc intermediate

• nature as hybrids of triphenylene and benzo[b]phosphole. Keywords: C–H functionalization; fluorescence; phosphole; polycyclic aromatic hydrocarbons; triphenylene; Introduction The phosphorus-containing five-membered ring, phosphole, has attracted significant attention as a structural motif in π

• phosphole oxides through C–H functionalization and cross-coupling reactions. The phosphole ring was constructed in the early stage of the synthesis by a three-component assembly method featuring a 1,4-cobalt migration as the key step. Unlike other C–H activation/alkyne annulation approaches to benzo[b

Recent advances in photocatalyzed reactions using well-defined copper(I) complexes

• Mingbing Zhong,
• Xavier Pannecoucke,
• Philippe Jubault and
• Thomas Poisson

Beilstein J. Org. Chem. 2020, 16, 451–481, doi:10.3762/bjoc.16.42

• -functionalization of alcohol using N-alkoxyphthalimide derivatives and glycine esters under basic or acidic conditions, respectively [42]. With regards to the α-functionalization, various N-arylated glycine esters were used as reaction partners with a broad range of N-alkoxyphthalimide derivatives, using [Cu(I)(dmp

• hydrogen phosphate ((R)-BNDHP) under similar reaction conditions and using the same copper catalyst provided the δ-functionalization of the alcohol (Scheme 28). This reaction manifold was applied to a large variety of N-alkoxyphthalimide derivatives using glycine ester derivatives and was also extended to

• more complex structures, including di- and tripeptides. These examples demonstrated the synthetic utility of the methodology. The reaction pathway was explained as follows by the authors: Similarly to the α-functionalization, the excited copper photocatalyst reduces the N-alkoxyphthalimide. Then, in

Photophysics and photochemistry of NIR absorbers derived from cyanines: key to new technologies based on chemistry 4.0

• Bernd Strehmel,
• Christian Schmitz,
• Ceren Kütahya,
• Yulian Pang,
• Anke Drewitz and
• Heinz Mustroph

Beilstein J. Org. Chem. 2020, 16, 415–444, doi:10.3762/bjoc.16.40

• at FEW Chemicals GmbH, Technikumstraße 1, D-06766 Bitterfeld-Wolfen, Germany 10.3762/bjoc.16.40 Abstract Cyanines derived from heptamethines were mainly discussed regarding their functionalization to broaden the solubility in different surroundings exhibiting either hydrophilic or hydrophobic

• also facilitated replacement of the substituent at the meso-position. Scheme 3 shows the activation of the carbon at this position by the chlorine substituent. This explains why functionalization of cyanine pattern by either electron withdrawing or electron donating substituents easily proceeds. It

• also enabled the introduction of reactive groups such as -N=C=S facilitating them to function as marker in biological/imaging applications [9]. This reaction occurred with good yields and extended the use of such NIR absorbers in more fields [1][2][7][8][9]. In general, this functionalization resulted

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• , Nagoya, 464-8602, Japan 10.3762/bjoc.16.37 Abstract Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium

• produces undesired cyclic compounds [14]. To design and synthesize a variety of HBC derivatives, methods for regioselective functionalization of HBC are in strong demand. As for functional groups on the HBC core, the introduction of halogen and boryl groups is an effective way to enable further

• functionalization [15]. Perchlorination was reported to functionalize HBC directly (Figure 1a) [16], and perchlorinated HBC was utilized for the formation of multiply functionalized HBC derivatives [17][18]. Other than perchlorination, hexaiodinated HBC was employed in subsequent reactions to introduce substituents

Room-temperature Pd/Ag direct arylation enabled by a radical pathway

• Amy L. Mayhugh and
• Christine K. Luscombe

Beilstein J. Org. Chem. 2020, 16, 384–390, doi:10.3762/bjoc.16.36

• both high molecular weight and regioregularity, and elevated reaction temperatures are typically required [3]. Mild conditions for C–H functionalization is of growing interest within the broader synthetic community as an opportunity to improve functional group tolerance, and environmental impact [4][5

• . There are limited examples across the aryl C–H functionalization literature indicating a transition metal-catalyzed radical process, limited largely to cobalt catalysis [31][32]. While there are several reports of palladium-catalyzed systems for room-temperature direct arylation (i.e., no directing

• Center for Selective C–H Functionalization (CHE-1700982).

Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3’,2’-e]pyridines (BBZFPys)

• Ryo Takishima,
• Yuji Nishii,
• Tomoaki Hinoue,
• Yoshitane Imai and
• Masahiro Miura

Beilstein J. Org. Chem. 2020, 16, 325–336, doi:10.3762/bjoc.16.32

• the ease of site-selective functionalization. Up to date, many BINOL-based CPL active compounds have been established by installing aromatic subunits on the periphery of the binaphthyl skeleton or on the hydroxy groups [25][26][27][28][29][30][31][32], extending the π-system [33], and linearly

• ’-binaphthyl backbone as precursors for the dehydrogenative coupling reaction (Scheme 2). In general, functionalization of the BINOL hydroxy groups should be performed at temperatures below 80 °C to prevent racemization [40][41]. 6,6’-Di-tert-butyl-1,1’-bi-2-naphthol (1) was treated with 2,6-difluoropyridine

Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations

• Rafia Siddiqui and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26

• research topic in modern synthetic organic chemistry for the constructions of challenging bonds, having the foremost scope in academia, pharmacy, and industry. Therefore, the development of green, simpler, and effective methodologies to accomplish direct C–H bond functionalization is well overdue and

• of photoredox catalysts for the functionalization of inert bonds in the domain of synthetic organic chemistry. Keywords: dual catalysis; light; ortho and para C–H bond functionalization; photoredox catalysis; Introduction Over a short period of time, direct C–H bond functionalizations by photoredox

• functionalizations. Herein, we will broadly discuss the different catalytic systems that facilitate ortho and para C–H functionalization by utilization of effective and feasible photoredox catalysts (with the aid of transition metals), hydrogen atom transfer, and aerobic oxidation. Over the last two decades, direct

Copper-catalyzed enantioselective conjugate addition of organometallic reagents to challenging Michael acceptors

• Delphine Pichon,
• Jennifer Morvan,
• Christophe Crévisy and
• Marc Mauduit

Beilstein J. Org. Chem. 2020, 16, 212–232, doi:10.3762/bjoc.16.24

• enantioselective synthesis of valnoctamide, a commercialized mild tranquilizer. Finally, this methodology was extended to the sequential Michael/halogenation reaction using NFSI or NCS as electrophiles, with similar efficiency. Similarly, a cocatalyzed enantioselective β-functionalization of enals was developed by