Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

• shed light on future directions for further development in this field. Keywords: bicyclic alkenes; cascade; catalysis; domino; transition-metal-catalyzed; Introduction A well-orchestrated sequence of events – cascade, also known as domino, tandem, and sequential reactions, constitutes a fascinating

• final product 195a. In 2019, the Shao group reported the Rh/Zn-catalyzed domino ARO/cyclization of oxabenzonorbornadienes 30 with phosphorus ylides 201 (Scheme 35) [83]. Despite the difficulty of using phosphorus ylides as nucleophiles in metal-catalyzed reactions due to their ability to strongly bind

• Austin Pounder Eric Neufeld Peter Myler William Tam Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada 10.3762/bjoc.19.38 Abstract This review presents a comprehensive overview of transition-metal

Transition-metal-catalyzed C–H bond activation as a sustainable strategy for the synthesis of fluorinated molecules: an overview

• Louis Monsigny,
• Floriane Doche and
• Tatiana Besset

Beilstein J. Org. Chem. 2023, 19, 448–473, doi:10.3762/bjoc.19.35

• approaches, the transition-metal-catalyzed functionalization of various scaffolds with a panel of fluorinated groups (XRF, X = S, Se, O) offered straightforward access to high value-added compounds. This review will highlight the main advances made in the field with the transition-metal-catalyzed

• retrosynthetic disconnections. In this context, a strong interest from the scientific community was shown towards the challenging synthesis of fluorinated molecules by transition-metal-catalyzed C–H bond activation [44][45][46][47][48][49][50], allowing the functionalization of complex molecules and even for

• (e.g., SCF3, SeCF3, SCF2CO2Et, OCH2CF3) by transition-metal-catalyzed C–H bond activation (Scheme 1). The review will be organized in two main parts, dedicated to the construction of a C–SCF2R/SeCF3 and C–OCH2CF3 bond. This review does not aim to be exhaustive and key examples were carefully chosen to

Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

Friedel–Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs)

• Swantje Lerch,
• Stefan Fritsch and
• Thomas Strassner

Beilstein J. Org. Chem. 2023, 19, 212–216, doi:10.3762/bjoc.19.20

• acylation; homogeneous catalysis; ionic liquids; iron catalysis; TAAILs; Introduction The Friedel–Crafts acylation is one of the oldest metal-catalyzed reactions in organic chemistry [1] and allows for the synthesis of a broad range of diverse compounds [2][3][4][5]. Starting from electron-rich aromatic

Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones

• Benedikt Kolb,
• Daniela Silva dos Santos,
• Sanja Krause,
• Anna Zens and
• Sabine Laschat

Beilstein J. Org. Chem. 2023, 19, 176–185, doi:10.3762/bjoc.19.17

• ethers 12 [19] and metal-catalyzed cross coupling of alkenes 13 and enones 14 [20][21] have been reported. However, these reactions face multiple disadvantages such as limited substrate scope, use of hazardous solvents and harsh reaction conditions such as high temperatures or acidic/basic conditions

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry

• Eric Gayon,
• Guillaume Lefèvre,
• Olivier Guerret,
• Adrien Tintar and
• Pablo Chourreu

Beilstein J. Org. Chem. 2023, 19, 158–166, doi:10.3762/bjoc.19.15

• to overall processes with a low atom economy, generating a significant amount of chemical waste, and which can be expensive when noble metals such as palladium salts are required (Scheme 1). The high efficiency of transition-metal-catalyzed cross-coupling methods in C–C bond formation processes

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• untapped potential in this area of research, and expect the utility of these building blocks to grow in the coming years. In particular, the recently established options to elaborate and functionalize 1,4-dithianes using mild transition-metal-catalyzed couplings, and their use in cycloaddition reactions

Practical synthesis of isocoumarins via Rh(III)-catalyzed C–H activation/annulation cascade

• Qian-Ci Gao,
• Yi-Fei Li,
• Jun Xuan and
• Xiao-Qiang Hu

Beilstein J. Org. Chem. 2023, 19, 100–106, doi:10.3762/bjoc.19.10

• for the synthesis of isocoumarin scaffolds. Traditional synthetic strategies including 1) intramolecular cyclization of 2-alkenyl benzoic acids or o‑alkynylbenzoates (Scheme 1b, I) [6][7][8][9][10], 2) oxidation of isochromans (Scheme 1b, II) [11][12], or 3) metal-catalyzed cross-coupling/cyclization

• of 1,2-difunctionalized arenes with alkynes or carbon monoxide (Scheme 1b, III) [13][14][15][16], have been widely applied for the assembly of isocoumarins over the past decades. Recently, the transition-metal-catalyzed ortho C–H activation/annulation of benzoic acids has emerged as an attractive

• , delivering a variety of structurally diverse isocoumarins in an efficient manner (3aa–qa, 43–82%). It is worth mentioning that the tolerance of halogen substituents (Cl, Br and I) may open up a new opportunity for further transition-metal-catalyzed cross-coupling reactions. Sensitive groups, such as ester

Two-step continuous-flow synthesis of 6-membered cyclic iodonium salts via anodic oxidation

• Julian Spils,
• Thomas Wirth and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 27–32, doi:10.3762/bjoc.19.2

• blocks for the synthesis of natural products [16][17][18][19][20][21]. One subclass of HVIs is diaryliodonium salts (DIS), which have been used as versatile electrophilic arylation reagents in metal-catalyzed and metal-free reactions [22][23]. The corresponding cyclic diaryliodonium salts (CDIS) have

Combining the best of both worlds: radical-based divergent total synthesis

• Kyriaki Gennaiou,
• Antonios Kelesidis,
• Maria Kourgiantaki and
• Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

• groups developed an approach using an unprecedented ring distortion. Their strategy consisted of a metal-catalyzed HAT to the exo-Δ-alkene of the 5/5/6/5 tetracycle 109, so as to subsequently favor a Dowd–Beckwith rearrangement [58] towards the tetraquinane skeleton of 112 (Scheme 9). The synthesis

Total synthesis of grayanane natural products

• Nicolas Fay,
• Rémi Blieck,
• Cyrille Kouklovsky and
• Aurélien de la Torre

Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181

• promoted by EtAlCl2. Two separable alkene regioisomers 54 and 55 were obtained in 19% and 50% yield, respectively. A metal-catalyzed hydrogen atom transfer (MHAT) allowed 54 to be partially converted to 55 via Shenvi’s isomerization [37]. Selective TBS protection on the bicyclo[3.2.1]octane moiety and

An alternative C–P cross-coupling route for the synthesis of novel V-shaped aryldiphosphonic acids

• Stephen J. I. Shearan,
• Enrico Andreoli and
• Marco Taddei

Beilstein J. Org. Chem. 2022, 18, 1518–1523, doi:10.3762/bjoc.18.160

• order of addition of reactants to perform the transition-metal-catalyzed C–P cross-coupling reaction, often referred to as the Tavs reaction, employing NiCl2 as a pre-catalyst in the phosphonylation of aryl bromide substrates using triisopropyl phosphite. This new method was employed in the synthesis of

• often either non-porous or have low porosity and have little to no long-range order. The idea here was that the V-shaped linkers, as well as different substituents attached to nitrogen, could potentially force a non-layered porous structure. Conventionally, the transition-metal-catalyzed C–P cross

Design, synthesis, and evaluation of chiral thiophosphorus acids as organocatalysts

• Karen R. Winters and
• Jean-Luc Montchamp

Beilstein J. Org. Chem. 2022, 18, 1471–1478, doi:10.3762/bjoc.18.154

• later to make the synthesis more modular, and the resolution is straightforward late in the synthesis. Additionally, the presence of the nitro group in CPA 2 was chosen for two reasons: 1) the possibility to further functionalize at this position through reduction, diazotization, and metal-catalyzed

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• , parallel/combinatorial synthesis, multicomponent chemistry, metal-catalyzed coupling reactions as well as NMR, preparative/analytical liquid chromatography and mass spectrometry). – An improved understanding of molecular pharmacology along with in vitro or in vivo assays to detect various aspects of drug

Synthesis and electrochemical properties of 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes

• Almaz A. Zagidullin,
• Farida F. Akhmatkhanova,
• Mikhail N. Khrizanforov,
• Robert R. Fayzullin,
• Tatiana P. Gerasimova,
• Ilya A. Bezkishko and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1338–1345, doi:10.3762/bjoc.18.139

• transition metal-catalyzed cross-coupling reactions broadly used for the preparation of different diarylacetylenes and, rarely, bis(chlorophenyl)acetylenes. Next, starting substituted benzaldehydes were treated with an excess of SOCl2 for 24 h at 25 °C. Corresponding substituted benzal chlorides 4 were

Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• reaction of hydrazones and p-benzoquinones [16], and Co3+/Cu2+-catalyzed C−N/N−N coupling of imidates with anthranils as both aminating reagents and organic oxidants [17]. Additional established routes to 1H-indazoles comprise transition metal‐catalyzed [18][19][20] and metal-free [21][22] intramolecular

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

• halides are valuable compounds with potent bioactivities [1][2][3][4][5] (Figure 1) and are utilized as crucial precursors for various metal-catalyzed cross-coupling reactions [6][7][8][9]. They are frequently used as synthetic intermediates in several value-added syntheses of natural products

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• attention [15][19][20][21][22][23][24][25][26]. This method involves a transition-metal-catalyzed one-pot, three-component reaction in which two functional groups are simultaneously introduced on the Se atom via double selenation. As examples, the following Cu-catalyzed one-pot reactions have been reported

Copper-catalyzed multicomponent reactions for the efficient synthesis of diverse spirotetrahydrocarbazoles

• Shao-Cong Zhan,
• Ren-Jie Fang,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 796–808, doi:10.3762/bjoc.18.80

• underwent a [4 + 2] cycloaddition reaction (reaction 1 in Scheme 1) [69][70][71][72][73][74]. This metal-catalyzed one-pot reaction not only combined the advantages of a traditional Diels–Alder reaction and the recently developed multicomponent reactions, but also meets the goal of green and sustainable

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• ; N-halosuccinimide; palladium(II); Introduction Electrophilic aromatic substitution [1][2][3] and ligand-directed transition-metal-catalyzed reactions [4][5][6][7][8] are among the most widely used synthetic approaches for the preparation of halogenated arenes. They are important precursors in cross

Tosylhydrazine-promoted self-conjugate reduction–Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives

• Sayan Pramanik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 469–478, doi:10.3762/bjoc.18.49

• , 3o, 3q, 3s, 3t and 3x) gave a good yield of the corresponding product, respectively. Here also, the halo-substituted aryl ring on 1 can be further used for transition-metal-catalyzed cross coupling reactions, thus providing a very good application. Then the effect of N-protecting groups on the

Iridium-catalyzed hydroacylation reactions of C1-substituted oxabenzonorbornadienes with salicylaldehyde: an experimental and computational study

• Angel Ho,
• Austin Pounder,
• Krish Valluru,
• Leanne D. Chen and
• William Tam

Beilstein J. Org. Chem. 2022, 18, 251–261, doi:10.3762/bjoc.18.30

• the art and science of selective molecular engineering [1]. To date, organic synthesis has largely been governed by the interconversion of pre-existing functional groups through the use of more traditional transition-metal-catalyzed cross-coupling reactions [2][3][4][5]. Although these reactions have

• attractive. Transition-metal-catalyzed reactions of strained bicyclic derivatives have been an intense area of research in the last 20 years (Scheme 1) [14][15][16][17]. Of particular interest is oxabenzonorbornadiene (OBD, 1), as it bears multiple points of reactivity that allow for diverse

• reported metal-catalyzed reactions of heterobicyclic alkenes and applications towards the synthesis of biologically active compounds (top). Representative examples of regioselectivity in different metal-catalyzed ring-opening reactions of C1-substituted oxabenzonorbornadiene derivatives (bottom left

Organocatalytic asymmetric nitroso aldol reaction of α-substituted malonamates

• Ekta Gupta,
• Narendra Kumar Vaishanv,
• Sandeep Kumar,
• Raja Krishnan Purshottam,
• Ruchir Kant and
• Kishor Mohanan

Beilstein J. Org. Chem. 2022, 18, 217–224, doi:10.3762/bjoc.18.25

• using a silver-BINAP catalyst combination [25]. Later, the same group could successfully tune the catalytic system to control the regioselectivity in the addition of metal enolate to nitrosoarenes to achieve an α-hydroxyamination [26]. Since then, several groups have shown the use of metal-catalyzed

• metal-catalyzed reactions [31][32][33][34][35][36]. The most successful among them are the ʟ-proline-catalyzed reactions of enolizable aldehydes with nitrosoarenes [37][38][39][40][41][42][43]. Besides ʟ-proline and its derivatives, various secondary amines derived from BINOL and cinchona alkaloids were

Earth-abundant 3d transition metals on the rise in catalysis

• Nikolaos Kaplaneris and
• Lutz Ackermann

Beilstein J. Org. Chem. 2022, 18, 86–88, doi:10.3762/bjoc.18.8

• alternatives. Furthermore, metal-catalyzed cross-couplings do require prefunctionalizations on both substrates and generate stoichiometric quantities of undesired chemical waste, thus reducing the sustainability of these catalytic transformations. To address these major limitations, the past decades have

• witnessed major momentum in metal-catalyzed C–H activation [4][5] as a more resource-economical strategy. This approach involves the efficient and selective cleavage of otherwise inert, yet omnipresent C–H bonds. This strategy avoids a variety of steps and reduces the amount of chemical waste. Very recently

• laboratories calls for a critical analysis of these methods to enable an efficient transition of these methods. Hence, manganese-catalyzed C–H functionalization for late-stage functionalizations of biomolecules and drug-like scaffolds are summarized [8]. Likewise, 3d transition metal-catalyzed C–H

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

• demanded the need of an alternative method for the synthesis of nitriles. Nowadays transition-metal-catalyzed reactions have received tremendous interest. Various transition metals such as Fe [15], Co [16], Ni [17], Pd [18], Cu [19], Rh [20] etc. were well explored in cyanation owing to its cost-effective

• achieved significant progress in recent times. Transition-metal-catalyzed cyanation reactions have emerged as an alternative approach to conventional cyanation strategies. Nowadays ruthenium has gained much acceptance owing to its wide range of oxidation states and ability to form a large number of