Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• SET with an electron acceptor (A), leading to PC•+ and A•−. The ground state photocatalyst is then regenerated by an SET reaction with an electron donor (D), affording also D•+. Both species described can be further involved in various organic transformations to form the target products (or byproducts

• applied cell potential. These divergent reactivity features make the two techniques totally complementary, allowing the exploration of a large portion of SET-driven organic transformations using at least one of them at a time. Since ‘radical ion’ conPET/e-PRC are proposed to involve the same radical ion

Aromatic C–H bond functionalization through organocatalyzed asymmetric intermolecular aza-Friedel–Crafts reaction: a recent update

• Anup Biswas

Beilstein J. Org. Chem. 2023, 19, 956–981, doi:10.3762/bjoc.19.72

• exclusively explored to assist substitutions of aromatic C–H bonds by other bonds and this area of research is more than a century old. However, many disadvantages are associated with metal-mediated organic transformations including harsh reaction conditions (e.g., high temperature) and toxic solvents. With

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• . Also, metal–NHC complexes have wide application in catalysis and various organic transformations and a range of metal–NHCs served as catalysts. In 2010, using NHC ligands, Yap and co-workers [90] developed a method for the direct para and meta-C–H alkenylation of pyridines with 4-octyne (107) using a

Sulfate radical anion-induced benzylic oxidation of N-(arylsulfonyl)benzylamines to N-arylsulfonylimines

• Joydev K. Laha,
• Pankaj Gupta and
• Amitava Hazra

Beilstein J. Org. Chem. 2023, 19, 771–777, doi:10.3762/bjoc.19.57

• their unique stability, defined reactivity, and versatility in organic synthesis [2]. Leveraging their electron-deficient nature, N-arylsulfonylimines are widely used in organic transformations including nucleophilic addition, cycloaddition, imino-aldol reaction, ene reactions, aza-Friedel–Crafts

Group 13 exchange and transborylation in catalysis

• Dominic R. Willcox and
• Stephen P. Thomas

Beilstein J. Org. Chem. 2023, 19, 325–348, doi:10.3762/bjoc.19.28

• and develop new catalytic processes, examples of which are the focus of this review. Keywords: catalysis; group 13 exchange; hydroboration; main group; transborylation; Introduction Group 13 compounds have found widespread use in stoichiometric organic transformations, typically in the

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• , we concluded that CH3CN and DMF were the ideal solvents for this transformation towards the effective formation of the product. As per literature reports, K2CO3 shows remarkable efficacy in various organic transformations [82]. Hence, this reaction was also examined under the influences of K2CO3 (2

Functionalization of imidazole N-oxide: a recent discovery in organic transformations

• Koustav Singha,
• Imran Habib and
• Mossaraf Hossain

Beilstein J. Org. Chem. 2022, 18, 1575–1588, doi:10.3762/bjoc.18.168

Lewis acid-catalyzed Pudovik reaction–phospha-Brook rearrangement sequence to access phosphoric esters

• Jin Yang,
• Dang-Wei Qian and
• Shang-Dong Yang

Beilstein J. Org. Chem. 2022, 18, 1188–1194, doi:10.3762/bjoc.18.123

• previously reported base-catalyzed transformations. Keywords: Lewis acid; phospha-Brook rearrangement; phosphoric esters; Pudovik reaction; Introduction Phosphoric esters are widely used in agrochemistry, biological sciences, clinical treatments, as well as in general organic transformations [1][2][3][4][5

Electrochemical hydrogenation of enones using a proton-exchange membrane reactor: selectivity and utility

• Koichi Mitsudo,
• Haruka Inoue,
• Yuta Niki,
• Eisuke Sato and
• Seiji Suga

Beilstein J. Org. Chem. 2022, 18, 1055–1061, doi:10.3762/bjoc.18.107

• environmentally benign organic transformations. Despite these advantages, the utility of PEM reactors in precise organic synthesis has long been unclear. Recently, however, Atobe and co-workers showed that PEM reactors can be used as a powerful and novel tool for precise organic synthesis [22][23][24][25][26

Automated grindstone chemistry: a simple and facile way for PEG-assisted stoichiometry-controlled halogenation of phenols and anilines using N-halosuccinimides

• Dharmendra Das,
• Akhil A. Bhosle,
• Amrita Chatterjee and
• Mainak Banerjee

Beilstein J. Org. Chem. 2022, 18, 999–1008, doi:10.3762/bjoc.18.100

• of mechanochemistry, Toda et al.’s “grindstone chemistry” [48] has also been proved as a useful technique for various organic transformations [49]. It is generally carried out by hand-grinding which is not only a labor-intensive process but also raises some concerns on the reaction kinetics

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

• Daniele Rocco,
• Ana A. Folgueiras-Amador,
• Richard C. D. Brown and
• Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

• cathodic reduction in a divided cell using flow electrochemistry technique, and to compare the results with the corresponding batch process. Once established, the flow electrochemistry NHC synthesis would be combined with applications as an organocatalyst in some organic transformations of cinnamaldehyde

Morita–Baylis–Hillman reaction of 3-formyl-9H-pyrido[3,4-b]indoles and fluorescence studies of the products

• Nisha Devi and
• Virender Singh

Beilstein J. Org. Chem. 2022, 18, 926–934, doi:10.3762/bjoc.18.92

• reaction has gained considerable attention from the past two decades as these MBH adducts are highly functionalized and offer various points of diversity. Due to these amazing features, these MBH adducts act as starting material on which various organic transformations can be performed leading to the

Palladium-catalyzed solid-state borylation of aryl halides using mechanochemistry

• Koji Kubota,
• Emiru Baba,
• Tamae Seo,
• Tatsuo Ishiyama and
• Hajime Ito

Beilstein J. Org. Chem. 2022, 18, 855–862, doi:10.3762/bjoc.18.86

• , mechanochemical synthesis using ball milling has attracted considerable attention as an efficient solvent-free synthetic technique [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Notably, the strong mechanical agitation provided by ball milling enables efficient solid-state organic

• transformations. Thus far, mechanochemical palladium-catalyzed cross-coupling reactions such as Suzuki–Miyaura [34][35][36][37][38][39][40][41][42][43][44][45][46][47], Buchwald–Hartwig [48][49][50][51][52], Sonogashira [53][54][55][56], Negishi [57], Mizoroki–Heck [58][59][60], and C–S bond-forming [61

Inductive heating and flow chemistry – a perfect synergy of emerging enabling technologies

• Conrad Kuhwald,
• Sibel Türkhan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2022, 18, 688–706, doi:10.3762/bjoc.18.70

• footprint, water features unique physicochemical properties at supercritical conditions. The five step synthesis of a typical antipsychotic drug iloperidone (80) is an impressive example of how supercritical water can be utilized as a privileged solvent in organic transformations (Scheme 14) [88]. Because

DDQ in mechanochemical C–N coupling reactions

• Shyamal Kanti Bera,
• Rosalin Bhanja and
• Prasenjit Mal

Beilstein J. Org. Chem. 2022, 18, 639–646, doi:10.3762/bjoc.18.64

• ten innovative technologies that IUPAC recognized [7]. To perform organic transformations in a greener way, the mechanochemical methods can also be considered as one of the alternative approaches [8][9][10]. The one-pot multicomponent synthesis of important heterocycles can be the state of art

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

• Prodip Howlader and
• Michael Schmittel

Beilstein J. Org. Chem. 2022, 18, 597–630, doi:10.3762/bjoc.18.62

• sometimes smart functionality describe a new class of supramolecular catalysts that are effective tools to control the activity and selectivity of organic transformations. Clearly, building heteroleptic assemblies provides an unprecedented flexibility towards controlling the dimension as well as

Synthesis of 5-unsubstituted dihydropyrimidinone-4-carboxylates from deep eutectic mixtures

• Sangram Gore,
• Sundarababu Baskaran and
• Burkhard König

Beilstein J. Org. Chem. 2022, 18, 331–336, doi:10.3762/bjoc.18.37

• ] based on carbohydrates, urea, and inorganic salts as an alternative to conventional solvents for carrying out a variety of organic transformations [32]. The stable melts are environmentally friendly as they are readily available from bulk renewable resources. Their simple production allows the

• replacement of organic solvents. The melts are stable against air and have very low vapor pressures resembling the properties of ionic liquids. In addition, the polarity of these melts is very high [33]. Recently, we have explored several organic transformations such as coupling reaction, cycloaddition

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• organic transformations [16]. The development of improved procedures in which less expensive and more suitable catalysts are used has remained an elusive goal. In this respect, iron catalysts stand out as valuable alternatives to those transition metals used in Sonogashira coupling reactions [17]. With

Efficient synthesis of ethyl 2-(oxazolin-2-yl)alkanoates via ethoxycarbonylketene-induced electrophilic ring expansion of aziridines

• Yelong Lei and
• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 70–76, doi:10.3762/bjoc.18.6

• groups in symmetric and asymmetric ligands widely applied in various organic transformations [7]. Especially, bisoxazolines are a kind of widely applied chiral ligands in diverse transition metal-participating asymmetric catalysis [8][9][10]. Several methods have been developed for the efficient

Recent advances and perspectives in ruthenium-catalyzed cyanation reactions

• Thaipparambil Aneeja,
• Cheriya Mukkolakkal Abdulla Afsina,
• Padinjare Veetil Saranya and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 37–52, doi:10.3762/bjoc.18.4

• reactive complexes of ruthenium and the high reusability and easy separation procedures of heterogeneous catalysts have proven the fact that this metal serve as highly effective catalyst for a wide range of organic transformations. It will surely motivate the scientific community to develop more

Solvent-free synthesis of enantioenriched β-silyl nitroalkanes under organocatalytic conditions

• Akhil K. Dubey and
• Raghunath Chowdhury

Beilstein J. Org. Chem. 2021, 17, 2642–2649, doi:10.3762/bjoc.17.177

• Enantioenriched organosilanes are attractive molecules in organic synthesis owing to their potential applications in stereoselective synthesis [1][2]. The unique sterical and electronical features of the C–Si bond can induce stereodifferentiation at the adjacent prostereogenic center in organic transformations [2

Visible-light-mediated copper photocatalysis for organic syntheses

• Yajing Zhang,
• Qian Wang,
• Zongsheng Yan,
• Donglai Ma and
• Yuguang Zheng

Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169

• homolysis to produce CuI species and radical intermediates. These intermediates can initiate productive organic transformations [39]. 2.1 Visible-light-mediated Cu(I) catalytic cycle Upon the absorption of a photon (Scheme 4), CuILn forms a singlet MLCT state, which subsequently yields the excited triplet

Photoredox catalysis in nickel-catalyzed C–H functionalization

• Lusina Mantry,
• Rajaram Maayuri,
• Vikash Kumar and
• Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2021, 17, 2209–2259, doi:10.3762/bjoc.17.143

• developments, which enables a diverse range of previously inaccessible organic transformations in milder reaction conditions [31][32][33][34][35][36][37][38][39][40]. Here, by absorbing visible light, a photocatalyst can function as a single-electron redox mediator through an oxidative or reductive quenching

A recent overview on the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles

• Pezhman Shiri,
• Ali Mohammad Amani and
• Thomas Mayer-Gall

Beilstein J. Org. Chem. 2021, 17, 1600–1628, doi:10.3762/bjoc.17.114

• Figure 1 [8][23][24][25][26][27]. As such, there is still a demand for the expansion of ways to access new 1,2,3-triazole heterocyclic rings in rapid, efficient, and versatile ways. Triazole rings could serve as important intermediates for numerous important organic transformations [28][29][30]. Diverse

A new and efficient methodology for olefin epoxidation catalyzed by supported cobalt nanoparticles

• Lucía Rossi-Fernández,
• Viviana Dorn and
• Gabriel Radivoy

Beilstein J. Org. Chem. 2021, 17, 519–526, doi:10.3762/bjoc.17.46

• relevant organic transformations [45][46][47][48][49][50][51][52], we report herein our study on the performance of CoNPs/MgO nanocatalyst for olefin epoxidation reactions. Compared to previous reports in the same field, it should be highlighted that our CoNPs/MgO catalyst is readily prepared from low-cost