Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives

• Loris Geminiani,
• Kathrin Junge,
• Matthias Beller and
• Jean-François Soulé

Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170

• hazardous diazonium salts and electron-rich arenes (mainly limited to phenols) [29][30][31], including metalated arenes [32][33]. The growing demand for structurally complex compounds across diverse applications has rendered the synthesis of non-symmetrical azoarenes with differently substituted azo bonds

Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules

• Wei Liu and
• Xiaoyu Yang

Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145

• catalytic kinetic resolution of racemic helical polycyclic phenols through an organocatalyzed enantioselective dearomative amination reaction [30]. The racemic polycyclic phenol derivatives 25, which exist as single diastereomers featuring both central chirality and helical chirality, were readily prepared

• aromatization process. Moreover, the terminal ring of the polycyclic phenol substrates was not limited to a pyranoid moiety as helical polycyclic phenols incorporating a furan ring also efficiently yielded both the dearomatized amination product (P,R,R)-28a and the recovered enantioenriched phenolic compound (M

• resolution of helical polycyclic phenols via CPA-catalyzed enantioselective aminative dearomatization reaction. Kinetic resolution of azahelicenes via CPA-catalyzed transfer hydrogenation. Asymmetric synthesis of planarly chiral macrocycles via CPA-catalyzed electrophilic aromatic amination. Enantioselective

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

• Feng Zhou,
• Chuansong Duanmu,
• Yanxing Li,
• Jin Li,
• Haiqing Xu,
• Pan Wang and
• Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

• technologies including ultrasonication, microwave irradiation, and microreaction technology into conventional nitration frameworks. Nikseresht et al. developed a novel heterogeneous heteropoly acid catalyst (PMA@MIL-53(Fe)), enabled efficient regioselective nitration of phenols under ultrasonic irradiation

Catalytic asymmetric reactions of isocyanides for constructing non-central chirality

• Jia-Yu Liao

Beilstein J. Org. Chem. 2025, 21, 1648–1660, doi:10.3762/bjoc.21.129

• -derived amino-phosphine L7 as the catalyst, a wide range of oxazole-containing tetra-ortho-substituted axially chiral phenols 47 bearing diverse scaffolds, including naphthyl-phenyl (e.g., 47a), phenyl-naphthyl (e.g., 47b), biphenyl (e.g., 47c), and binaphthyl (e.g., 47d), were obtained in high yields

• -squaramide bifunctional ligand L8 as the catalyst, a universal synthesis of tri- and tetra-ortho-substituted biaryl phenols 51 containing a thiazole moiety was achieved in 85–99% yield with 56–99% ee. It is worth mentioning that this work represents the first example of catalytic asymmetric DKR of biaryl

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

• 2020, Bull et al. published a short synthesis of 3-aryloxetan-3-carboxylic acids 152 employing a Friedel–Crafts alkylation (which builds on their previous alkylation of phenols [87]) and a selective furan oxidative cleavage (Scheme 37) [88]. The oxidation protocol uses a catalytic amount of a high

• access to a large library of functionalised oxetanes in moderate to excellent yields and under very simple reaction conditions, which are compatible with a wide range of nucleophiles including alcohols (primary, secondary and tertiary), phenols, aliphatic and aromatic amines or heteroaryls (e.g., furan

• 178 from 3-aryloxetan-3-ols through a tandem Friedel–Crafts alkylation/intramolecular ring opening (Scheme 45) [87]. The reaction was mostly high yielding and best results were obtained for electron-rich para-substituted phenols, while substituents in the ortho/meta-positions diverted the

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

• Betty A. Kustiana,
• Galuh Widiyarti and
• Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

Recent advances in the electrochemical synthesis of organophosphorus compounds

• Babak Kaboudin,
• Milad Behroozi,
• Sepideh Sadighi and
• Fatemeh Asgharzadeh

Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61

• formation In 2021, Zhong et al. [64] reported an electrochemical coupling reaction of phenols with dialkyl phosphonates. The reaction was carried out in an undivided cell using platinum electrodes in the presence of sodium iodide at a constant current. Various electrodes were examined, and the best results

• reaction proceeded with anodic oxidation of iodide to iodine, followed by a reaction with dialkyl phosphite to give I–P(O)(OR)2. The final product was formed by a simple nucleophilic substitution of phenols with I–P(O)(OR)2. In 2021, Wang et al. [65] presented a report on electrochemical P–O bond formation

• . Various phenols, including those with electron-neutral, electron-donating, and electron-withdrawing groups, were efficiently converted into the target products in high yields. Phenols containing condensed aromatic and heterocyclic rings were also identified as suitable starting materials. The reaction

Red light excitation: illuminating photocatalysis in a new spectrum

• Lucas Fortier,
• Corentin Lefebvre and
• Norbert Hoffmann

Beilstein J. Org. Chem. 2025, 21, 296–326, doi:10.3762/bjoc.21.22

• organoboron substrates 31, including -B(OH)2, -Bpin, -BF3K, and -Bneo (neopentyl borate) derivatives noted as “-[B]” in Scheme 11, to produce aliphatic alcohols and phenols 32 with moderate to excellent yields. The versatility of this method is highlighted by the broad substrate scope of more than 50 examples

• catalyst, which operates through a reductive quenching mechanism. A suitable reaction pathway was established, leading to moderate to excellent yields of the corresponding phenols 60 (Scheme 15). The reaction primarily involves the oxidation of iPr2NEt (DIPEA) by the excited photocatalyst 55 to generate

Cu(OTf)₂-catalyzed multicomponent reactions

• Sara Colombo,
• Camilla Loro,
• Egle M. Beccalli,
• Gianluigi Broggini and
• Marta Papis

Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7

• aldehydes and phenols. The mechanism involves the reaction of the azide with the hemiacetal XLII generated in situ from the aldehydes and alcohols, followed by coupling with the alkynes to form the triazole ring. Both, copper triflate and copper metal are essential for the success of the reaction. On the

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

• -catalysis recently led to an array of intriguing transformations. Axially chiral styrenes 26 were assembled via the NHC-catalyzed reaction of propargylic aldehydes 25, sulfinic acids, and phenols [28]. The crucial step of this transformation is the 1,4-addition of the sulfinic anion to the triple bond of

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• perfluorobenzene, perfluoropyridine, perfluoronaphthalene, decafluorobiphenyl, and many other synthesized perfluoroarenes, and the nucleophiles are also abundant and contain aryllithium, conjugated organic dilithium reagents, phenols and benzenethiols, etc. [35][36][37][38][39][40][41][42][43]. We recently

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• resulting C-centered radical A with tert-butylperoxy radical lead to the tert-butylperoxy cyclohexane 84. C(sp2)–X peroxidation of arenes The radical peroxidation of the aromatic core has been realized on the example of the peroxidation of phenols [83][84][85][86][87][88][89][90]. The first studies were

• carried out as part of the investigation of the enzymatic function of cytochrome P-450 with low valent ruthenium complex catalysts. Various phenols 86 bearing para-substituents were transformed into the corresponding tert-butyldioxy dienones 87 smoothly using RuCl2(PPh3)3 as the catalyst (Scheme 31) [83

• ][84][85]. The authors rationalized that RuCl2(PPh3)3 reacts with TBHP to give the (alkylperoxido)ruthenium(II) complex, which subsequently undergoes heterolytic cleavage of the O–O bond to form the (oxido)ruthenium(IV) species. HAT from the phenols by Ru(IV)=O intermediate leads to the phenoxyl

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• . A synthetic protocol for diaryl ethers via an in situ generation of a hypervalent iodine salt was introduced by Stuart and co-workers in 2020. To study the scope of the reaction first various substituted aryl(TMP)iodonium salts 12 were reacted with different substituted phenols 61 in the presence of

• 62, starting with aryl iodides and phenols 61. In this metal-free reaction, aryl(TMP)iodonium salts 12 were prepared in situ from aryl iodides via treatment with m-CPBA, TsOH, and TMB at 55 °C in acetonitrile, which subsequently react with the substituted phenols 61 to produce the O-arylated products

• reactions occurred under mild conditions and without any need of transition-metal catalysts. In 2023, Wu and colleagues successfully synthesized a range of meta-substituted biaryl ethers. The reaction involves phenols 61 and cyclic diaryliodonium salts 73, dissolved in tert-butyl alcohol, in the presence of

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• , resulting in the C2-dearomatized naphthalenone products 41a–d with high efficiency (Scheme 41). In addition, electron-rich phenols or nonfunctionalized 2-naphthols could also be used as nucleophiles, providing the desired chiral spirocycles 43a–e and 44a–e in good yields with excellent ee values (Scheme 42

• spiroannulation of 2-naphthols or electron-enriched phenols under mild conditions with excellent regioselectivities, enantioselectivities and diastereoselectivities (Scheme 44, 43a–g, 44a–q). In addition, the nucleophilic substitution–dearomative cyclization process between indoles and yne-allylic esters can also

• carbonates and 1,3-dicarbonyls. Proposed mechanism. Formal [4 + 1] annulations with amines. Formal [4 + 2] annulations with hydrazines. Proposed mechanism. Dearomative annulation of 1-naphthols and yne-allylic esters. Dearomative annulation of phenols or 2-naphthols and yne-allylic esters. Postulated

5th International Symposium on Synthesis and Catalysis (ISySyCat2023)

• Anthony J. Burke and
• Elisabete P. Carreiro

Beilstein J. Org. Chem. 2024, 20, 2704–2707, doi:10.3762/bjoc.20.227

• novel diketopyrrolopyrrole derivatives through versatile SNAr reactions between N,N’-bis(pentafluorobenzyl)-substituted diketopyrrolopyrrole and thiols and phenols under smooth conditions, resulting in the final compounds with satisfactory yields [20]. These newly synthesized compounds exhibited a high

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

• Yukiko Karuo,
• Keita Hirata,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

• fluoroenynes via Suzuki–Miyaura and Sonogashira cross-coupling reactions using novel multihalogenated fluorovinyl ethers, which are easily prepared from the reaction between phenols and 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane). These reactions make use of the unique structure of multihalogenated

• development of a dual-reactive fluorine-containing C2-unit, which was prepared from trifluoroethanol in two steps in 63% yield, allowed the convergent synthesis of fluoroalkenes (Scheme 1C) [26]. We recently found multihalogenated vinyl ethers 1 could be obtained by the reaction of phenols with 2-bromo-2

• -coupling between 1 derived from various phenols and 5a. Vinyl ethers 1b–d were converted into enynes 3t–v in 29–35% yields (Table 4, entries 19–21). The reaction using 1e, which bears an amino group on the benzene ring, did not complete despite requiring a long reaction time (Table 4, entry 22). Therefore

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

• Bhaskar B. Dhotare,
• Seema V. Kanojia,
• Chahna K. Sakhiya,
• Amey Wadawale and
• Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

• synthetic route. Results and Discussion Initially, 3-arylbenzofuran-2(3H)-ones 3aa–ma were prepared following a SbCl3-catalyzed Friedel–Crafts alkylation of phenols 1a–m with benzylic alcohols 2a–d, earlier reported by us (Scheme 1) [21][22][23]. All the synthesized 3-arylbenzofuran-2(3H)-ones were

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

• Alfiya R. Gimadieva,
• Yuliya Z. Khazimullina,
• Aigiza A. Gilimkhanova and
• Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

• : oxidation; 6-methyluracil; peroxydisulfate; phthalocyanine catalysts; pyridine; Introduction The Elbs and Boyland–Sims peroxydisulfate oxidation reactions offer a convenient means of introducing the hydroxy function into phenols and aromatic amines [1]. The oxidation of phenol using peroxydisulfate was

• compounds such as phenols, coumarins, pyridines, pyrimidines, quinolines, and others. This has resulted in the production of numerous valuable products. The reaction's appeal lies in its simplicity and the fact that there is no requirement to protect sensitive functional groups, thus making the introduction

• reactions was made. It has been suggested that a nucleophilic substitution of the peroxide oxygen atom occurs in peroxydisulfate [32]. Regarding phenols (Elbs reaction), there is also a nucleophilic substitution of the phenolate ion. For aromatic amines (Boyland–Sims reaction), a neutral nitrogen atom of

From perfluoroalkyl aryl sulfoxides to ortho thioethers

• Yang Li,
• Guillaume Dagousset,
• Emmanuel Magnier and
• Bruce Pégot

Beilstein J. Org. Chem. 2024, 20, 2108–2113, doi:10.3762/bjoc.20.181

• study, many research groups described a strategy for ortho-C–H functionalization of aryl sulfoxides with various nucleophiles via a cascade reaction of interrupted Pummerer reaction/sigmatropic rearrangement (Scheme 1a) [6][7][8][9][10][11]. A large range of nucleophiles, such as phenols [12][13][14][15

A new platform for the synthesis of diketopyrrolopyrrole derivatives via nucleophilic aromatic substitution reactions

• Vitor A. S. Almodovar and
• Augusto C. Tomé

Beilstein J. Org. Chem. 2024, 20, 1933–1939, doi:10.3762/bjoc.20.169

• synthesis of highly fluorescent DPP derivatives through straightforward nucleophilic aromatic substitution reactions with thiols and phenols. These nucleophilic substitutions occur at room temperature and manifest a remarkable selectivity for the 4-position of the pentafluorophenyl groups. Both symmetrical

• pentafluorobenzyl bromide, followed by a nucleophilic aromatic substitution (SNAr) with thiols and phenols. This approach is based on the well-established reactivity of perfluoroaromatic compounds in nucleophilic aromatic substitutions [32][33][34][35]. By varying the reaction conditions and the number of

• generating new DPP derivatives through nucleophilic aromatic substitution reactions with thiols and phenols. The main objective of this study was to employ the N,N’-bis(pentafluorobenzyl)-DPP 2 as an electrophile and investigate its reactivity with thiols and phenols (Scheme 1). All SNAr reactions were

Synthesis of polycyclic aromatic quinones by continuous flow electrochemical oxidation: anodic methoxylation of polycyclic aromatic phenols (PAPs)

• Hiwot M. Tiruye,
• Solon Economopoulos and
• Kåre B. Jørgensen

Beilstein J. Org. Chem. 2024, 20, 1746–1757, doi:10.3762/bjoc.20.153

• Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway 10.3762/bjoc.20.153 Abstract The electrochemical oxidation of polycyclic aromatic phenols (PAPs) has been developed in a microfluidic cell to synthesize polycyclic aromatic quinones (PAQs). Methanol was used as nucleophile to

• (PAHs) by cytochrome P450 (CYP) and other metabolic enzymes [7][8]. Main metabolic pathways form quinone isomers of benzo[a]pyrene [8], naphthalene [9][10], and benzene [11]. Numerous methods for the oxidation of phenols or their derivatives to quinones have been described [12]. Oxidation with Fremy’s

• reagents have been explored for the oxidation of polycyclic aromatic phenols (PAPs). Oxidation of 1-naphthol derivatives by bis(trifluoroacetoxy)iodobenzene (BTI) furnished p-naphthoquinones [16]. Other PAPs follow the same pattern forming p-quinones or o-quinones when the para-position is structurally

Chemo-enzymatic total synthesis: current approaches toward the integration of chemical and enzymatic transformations

• Ryo Tanifuji and
• Hiroki Oguri

Beilstein J. Org. Chem. 2024, 20, 1693–1712, doi:10.3762/bjoc.20.151

• oxidation of phenols on A- and E-rings, yield bisquinone 94. The membrane-bound peptidase SfmE excises the long-chain fatty acid moiety on the N-terminus of the C1 side chain. Secretion through the efflux pump SfmG, and extracellular oxidative deamination catalyzed by the berberine bridge enzyme (BBE)-like

Divergent role of PIDA and PIFA in the AlX₃ (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study

• Kevin A. Juárez-Ornelas,
• Manuel Solís-Hernández,
• Pedro Navarro-Santos,
• J. Oscar C. Jiménez-Halla and
• César R. Solorio-Alvarado

Beilstein J. Org. Chem. 2024, 20, 1580–1589, doi:10.3762/bjoc.20.141

• straightforward conditions (Scheme 1). The synthesis of aryl halides is of great academic and industrial importance. Recently, our research group has developed a new procedure for the ortho-selective chlorination of phenols under mild conditions in a short reaction time [26]. The chlorinating species was

• protocol for the electrophilic bromination of arenes, mainly phenols [28][29]. Accordingly, the bromination reaction was initially explored by mixing PIFA and AlBr3, which gave an acceptable yield (84%). However, other iodine(III) reagents were tested as oxidants during the optimization process. Thus, when

Synthesis of 2-benzyl N-substituted anilines via imine condensation–isoaromatization of (E)-2-arylidene-3-cyclohexenones and primary amines

• Lu Li,
• Na Li,
• Xiao-Tian Mo,
• Ming-Wei Yuan,
• Lin Jiang and
• Ming-Long Yuan

Beilstein J. Org. Chem. 2024, 20, 1468–1475, doi:10.3762/bjoc.20.130

• –dehydrogenative aromatization strategy with amines as nucleophiles [11][12]. For instance, the groups of Deng and Li reported the Pd catalyzed oxidative coupling of 2-cyclohexenones with amines [13]. Later, the same group demonstrated the direct amination of phenols by reductive coupling of in situ generated 2

Phenotellurazine redox catalysts: elements of design for radical cross-dehydrogenative coupling reactions

• Alina Paffen,
• Christopher Cremer and
• Frederic W. Patureau

Beilstein J. Org. Chem. 2024, 20, 1292–1297, doi:10.3762/bjoc.20.112

• , which exploit the redox flexibility of tellurium, especially in the context of phenotellurazine scaffolds. Notably, we showed that phenotellurazine PTeZ1 could significantly catalyze the cross-dehydrogenative phenothiazination of phenols bearing challenging electron-withdrawing substituents under a

• the Te(II)-catalyzed benchmark dehydrogenative phenothiazination of phenols, a reaction that we discovered in 2015 [35][36][37], under analogous conditions as previously described [30][31][32]. The results are summarized in Scheme 2. The multistep synthesis and characterization of all Te-based