Synthesis and properties of 6-alkynyl-5-aryluracils

• Ruben Manuel Figueira de Abreu,
• Till Brockmann,
• Alexander Villinger,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

• Abstract The development of a new and straightforward chemoselective method for the synthesis of uracil-based structures by combining Suzuki–Miyaura and Sonogashira–Hagihara cross-coupling is reported. The methodology was applied to synthesize a series of novel compounds. The tolerance of the combination

• this work, we report a new chemoselective method for the synthesis of a series of hitherto unknown uracil-based compounds by combining Suzuki–Miyaura and Sonogashira–Hagihara cross-coupling [60][61]. The method is designed to be flexible and could also be used to synthesize other structural motifs

• obtained. Compounds 3a–j were subsequently transformed to 5a–t by Suzuki–Miyaura cross-coupling. The bromination of 1 was performed by using Br2 (1 equiv), Ac2O (1.5 equiv), AcOH (25 °C, 1 h) and yielded the desired product in 52% [62]. With the starting material in hand, initial Sonogashira–Hagihara cross

Three-component N-alkenylation of azoles with alkynes and iodine(III) electrophile: synthesis of multisubstituted N-vinylazoles

• Jun Kikuchi,
• Roi Nakajima and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2024, 20, 891–897, doi:10.3762/bjoc.20.79

• Suzuki–Miyaura and Sonogashira couplings on 4aa or 4ba afforded the desired products 5 and 6 in 47% and 74% yields, respectively. In the former case, the C–Br bond on the pyrazole moiety remained intact, highlighting the superior leaving group ability of the BX group. Cu-catalyzed Ullmann coupling

Synthesis and biological profile of 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines, a novel class of acyl-ACP thioesterase inhibitors

• Jens Frackenpohl,
• David M. Barber,
• Guido Bojack,
• Birgit Bollenbach-Wahl,
• Ralf Braun,
• Rahel Getachew,
• Sabine Hohmann,
• Kwang-Yoon Ko,
• Karoline Kurowski,
• Bernd Laber,
• Rebecca L. Mattison,
• Thomas Müller,
• Anna M. Reingruber,
• Dirk Schmutzler and
• Andrea Svejda

Beilstein J. Org. Chem. 2024, 20, 540–551, doi:10.3762/bjoc.20.46

• synthetic route, which enabled us to introduce a methyl substituent in this position. Likewise, methyl-substituted thiazolo[4,5-b]pyridines 5, 15a, and 15c were synthesized using an optimized Suzuki coupling and served together with compounds 12a–c as key intermediates to explore different reagents and

Mono or double Pd-catalyzed C–H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives

• Nahed Ketata,
• Linhao Liu,
• Ridha Ben Salem and
• Henri Doucet

Beilstein J. Org. Chem. 2024, 20, 427–435, doi:10.3762/bjoc.20.37

• palladium-catalyzed direct intermolecular arylation, followed by a direct intramolecular arylation step. As the C–H bond activation of several benzene derivatives remains very challenging, the preparation of fluoranthenes from 1,8-dibromonaphthalene via Suzuki coupling followed by intramolecular C–H

• contrast, only a few examples of fluoranthene backbone preparation by Pd-catalyzed C–H arylation have been reported. Some examples of the preparation of this skeleton by Suzuki coupling followed by intramolecular C–H coupling have been described [18][19][20][21][22][23][24]. In 2017, Metin, Türkmen and co

• intermolecular Suzuki coupling with an intramolecular C–H arylation, it should be possible to access numerous fluoranthene derivatives from commercially available 1,8-dibromobenzene in a single manipulation (Scheme 1d). Here, we describe i) conditions enabling the annulative π-extension of 1,8-dibromonaphthalene

Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

• Carlos R. Azpilcueta-Nicolas and
• Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

• decarboxylative cross-coupling (DCC) of NHPI esters with organometallic reagents, resembling classic Kumada, Negishi, and Suzuki couplings, has been enabled by nickel (Ni), cobalt (Co), iron (Fe), and copper (Cu) catalysts [84][85][86][87][88][89][90][91] (Scheme 23A). The typical mechanism begins by

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• corresponding boronic acid 9 and a Suzuki–Miyaura cross-coupling between 8 and 9 gave rise to dimer 10, followed by the oxidation of both acenaphthene units into 1,8-naphthalic anhydrides. Installation of the thiepine ring was achieved by a double nucleophilic aromatic substitution induced by sodium sulfide

• corresponding bis(thiophenyl) thioether, which then underwent successive bromination and iodination to give intermediate 18. Next, a two-fold Suzuki–Miyaura cross-coupling occurring chemoselectively on the iodinated positions allowed the symmetric extension of the hydrocarbon scaffold, with the insertion of two

• thiepine via a two-fold Suzuki–Miyaura cross-coupling with 1,2-phenylenediboronic pinacol ester. The resulting S-doped extended tribenzothiepine 21 proved stable under ambient conditions for several months and exhibited good solubility in common organic solvents, which is ascribed to the boat-shape

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• through scanning tunneling microscopy [85]. For TCBDs bearing unsubstituted anilino (p-H2NC6H4–) groups, their conversion into the p-iodophenyl derivatives via the Sandmeyer reaction and subsequent post-functionalization via the Suzuki and Sonogashira coupling reactions are achieved [86]. In the reaction

Controlling the reactivity of La@C₈₂ by reduction: reaction of the La@C₈₂ anion with alkyl halide with high regioselectivity

• Yutaka Maeda,
• Saeka Akita,
• Mitsuaki Suzuki,
• Michio Yamada,
• Takeshi Akasaka,
• Kaoru Kobayashi and
• Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

• Yutaka Maeda Saeka Akita Mitsuaki Suzuki Michio Yamada Takeshi Akasaka Kaoru Kobayashi Shigeru Nagase Department of Chemistry, Tokyo Gakugei University, Koganei, Tokyo 184-8501, Japan Department of Chemistry, Josai University, Sakado, Saitama 350-0295, Japan Tsukuba Advanced Research Alliance

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

• Recep Isci and
• Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

• 4-bromo-N,N-diphenylaniline (5) with n-butyllithium at −78 °C and addition of 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. The Suzuki-coupling reaction of TT 4 with borolane 6 produced the intermediate 7 in 81% yield. The target D–π–A-type fluorophore, DMB-TT-TPA (8), was produced by

Substituent-controlled construction of A₄B₂-hexaphyrins and A₃B-porphyrins: a mechanistic evaluation

• Seda Cinar,
• Dilek Isik Tasgin and
• Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

• mentioned by Osuka and Suzuki [13], besides the formation of A3B-porphyrins. On the other hand, electron-withdrawing but less bulky (4-trifluoromethylphenyl) groups on tripyrrane 5 led to predominant formation of the A3B-porphyrin even when it was reacted with mono-, di-, or penta-substituted aryl N

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• )diboron catalyzed by Pd(dpf)Cl2/KOAc. Finally, TPECNz was obtained as red solid in a reasonable yield by a Suzuki-type cross-coupling reaction between 3 and 4,9-dibromonaphtho[2,3-c][1,2,5]thiadiazole. The chemical structure and purity of compound 3 were verified by 1H NMR, 13C NMR, and high-resolution

Synthesis and biological evaluation of Argemone mexicana-inspired antimicrobials

• Jessica Villegas,
• Bryce C. Ball,
• Katelyn M. Shouse,
• Caleb W. VanArragon,
• Ashley N. Wasserman,
• Hannah E. Bhakta,
• Allen G. Oliver,
• Danielle A. Orozco-Nunnelly and
• Jeffrey M. Pruet

Beilstein J. Org. Chem. 2023, 19, 1511–1524, doi:10.3762/bjoc.19.108

• complete decomposition. With the desired naphthylamines in hand, we were able to complete our synthesis of four chelerythrine variants as shown in Scheme 7. After N-formylation providing intermediates 11 and 12 in good yield, a three-step sequence was performed: Suzuki coupling of the aryl bromide with one

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• electrophilic trapping of the intermediary indole anion with alkyl halides provides a concise one-pot synthesis of 3-iodoindoles. The latter are valuable substrates for Suzuki arylations, which are exemplified with the syntheses of four derivatives, some of them are blue emitters in solution and in the solid

• alkynyl-substituted 3-iodoindole 6 as product in 42% isolated yield in the sense of a pseudo-five-component reaction (Scheme 3). Finally, the 3-iodoindole 5a and arylboronic acids 7 were employed in a standard Suzuki protocol with cesium carbonate as a base to give rise to the formation of 1,2,3

• N-iodosuccinimide prior to N-alkylation to give substituted 3-iodoindoles in a concise consecutive four-component fashion in modest to good yields. These target compounds are versatile building blocks for instance for a Suzuki coupling to give 1-alkyl-2,3-diarylindoles that can be of particular

Non-noble metal-catalyzed cross-dehydrogenation coupling (CDC) involving ether α-C(sp³)–H to construct C–C bonds

• Hui Yu and
• Feng Xu

Beilstein J. Org. Chem. 2023, 19, 1259–1288, doi:10.3762/bjoc.19.94

• Negishi reaction (Zn) [1], Stille reaction (Sn) [2], Kumada reaction (Mg) [3], and Suzuki reaction (Pd) [4] (Scheme 1a). However, these coupling reactions involve a metal exchange step that generates a considerable amount of reaction waste, such as metal salts, which are not environmentally friendly. To

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

• . Notably, carbonylative amidation of a borylated aryl bromide to 26d proceeded well, where a Pd-catalyzed carbonylative amidation reaction would be plagued by undesired Suzuki coupling. Several secondary cyclic and acyclic amines, as well as primary amines were successfully employed as amine coupling

Construction of hexabenzocoronene-based chiral nanographenes

• Ranran Li,
• Di Wang,
• Shengtao Li and
• Peng An

Beilstein J. Org. Chem. 2023, 19, 736–751, doi:10.3762/bjoc.19.54

• ]azepine and tetrabromothiophene-S,S-dioxide, followed by oxidative aromatization in the presence DDQ to afford compound 25 in an overall 75% yield. Suzuki−Miyaura cross-coupling reaction of compound 25 with (4-ethylphenyl)boronic acid in the presence of Pd(CH3CN)2Cl2, SPhos, and K3PO4 then furnished the

• the prefused building block in a 49% yield. Then naphthalene and phenanthrene residues were introduced into compound 33 through Suzuki coupling reaction, the corresponding precursors 34 and 36 were obtained respectively in high yields. The final cyclodehydrogenation using DDQ and TfOH proceeded

• benzo[b]naphtho[2,3-f]oxepine 66 with tetrabromothiophene-S,S-dioxide in toluene followed by oxidative aromatization in the presence of DDQ afforded tetrabrominated aromatics 67 in an 81% yield. Subsequently, fourfold Suzuki–Miyaura cross-coupling of polybrominated compound 67 was performed, affording

Strategies in the synthesis of dibenzo[b,f]heteropines

• David I. H. Maier,
• Barend C. B. Bezuidenhoudt and
• Charlene Marais

Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51

• . through a multicomponent reaction system [57]. The authors provided a series of substituted derivatives through Pd/Rh-catalysed domino coupling. The reaction proceeded via a Suzuki coupling, followed by an in situ Buchwald–Hartwig amination. The authors reported moderate to good yields in a series with

• electron-donating and electron-withdrawing groups, as well as N-aryl and N-alkylamines (Scheme 15). Lam et al. [58] expanded on the multicomponent method to form substituted dihydropyridobenzazepines 80–82 wherein vinylpyridines 77 are coupled with boronate ester anilines 78 in a Suzuki reaction

• towards dibenzo[b,f]azepines and other dibenzo[b,f]heteropines, and the functionalisation thereof. Modern metal-catalyzed methods to introduce the C–C bridge include the Heck reaction, the Sonogashira reaction, Suzuki coupling and ring-closing metathesis, whereas Buchwald–Hartwig type reactions and Ullman

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

• reactions, which witnessed considerable development in the last two decades [14], several cross-coupling methodologies involving soft nucleophiles, such as iron-mediated Suzuki–Miyaura cross-couplings, being reported [15]. The introduction of alkyl–alkenyl linkage by means of iron-catalyzed cross-coupling

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

• –cyclization of common synthetic intermediates 94 and 95 (Scheme 8). Compound 94 was obtained in three steps, with the key step being the Suzuki–Miyaura coupling of appropriately functionalized precursors 91 and 92 using Romo and co-worker’s protocol [52]. Reaction of 94 under PPTS acidic conditions initiated

• substitution for the minimization of 1,3-allylic strain to enable Suzuki coupling for biaryl formation as a single atropisomer. The optimized conditions for this transformation utilize Buchwald’s catalyst (SPhos and Pd-based G2 precatalyst) in conjunction with K3PO4. With DBCOD bearing carboxylic acid handles

Inline purification in continuous flow synthesis – opportunities and challenges

• Jorge García-Lacuna and
• Marcus Baumann

Beilstein J. Org. Chem. 2022, 18, 1720–1740, doi:10.3762/bjoc.18.182

• obtain the pure compound that met the requirements (>99.5%) [41]. Another very recent report which couples a Suzuki–Miyaura reaction with inline purification, uses capture-SMB technology as its purification approach [42] (Table 2, entry 2). The crude material is directed into two twin C-18 columns that

• reported by Pitts and collaborators. This study achieves full removal of metal species after common homogenous catalytic reactions such as a Suzuki–Miyaura reaction, Sonogashira reaction or hydrogenation mediated by Wilkinson’s catalyst [84]. Other interesting examples to remove transition metals in

• successfully coupled to a Suzuki–Miyaura reaction [119]. Crystallization was identified as a suitable purification technique to separate products from unreacted starting materials while avoiding metal contamination. Water was used as antisolvent and two mixing units were needed in the crystallization process

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

• diastereoselectivity in 58% on a 3 g scale. Subsequently, vinyl halide 48 was converted to diene 50 by Suzuki coupling with potassium vinyltrifluoroborate (49) in 90% yield (Scheme 8). The C7–C8 bond formation from a bridgehead carbocation was a real challenge to close the 7-membered ring. To achieve this, the

Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane)

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

Beilstein J. Org. Chem. 2022, 18, 1567–1574, doi:10.3762/bjoc.18.167

• presence of KOH. In this reaction, halothane plays a key role in the construction of highly halogenated and structurally intriguing products. The tri-halogenated alkenyl ether has potential applications in organic chemistry, e.g., in Suzuki–Miyaura or Sonogashira cross-coupling reactions. Further

Electrogenerated base-promoted cyclopropanation using alkyl 2-chloroacetates

• Kouichi Matsumoto,
• Yuta Hayashi,
• Kengo Hamasaki,
• Mizuki Matsuse,
• Hiyono Suzuki,
• Keiji Nishiwaki and
• Norihito Kawashita

Beilstein J. Org. Chem. 2022, 18, 1116–1122, doi:10.3762/bjoc.18.114

• Kouichi Matsumoto Yuta Hayashi Kengo Hamasaki Mizuki Matsuse Hiyono Suzuki Keiji Nishiwaki Norihito Kawashita Department of Chemistry, School of Science and Engineering, Kindai University 3-4-1 Kowakae, Higashi-osaka, Osaka 577-8502, Japan Department of Pharmaceutical Sciences, Faculty of Pharmacy

Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• [34], dibromodithienothiophene 24 is lithiated with n-butyllithium at −90 °C, and the resulting species is reacted in situ with triisopropyl borate. After aqueous workup, dithieno[3,2-b:2’,3’-d]thiophene-2,6-diylboronic acid (25) is obtained, enabling subsequent Suzuki–Miyaura cross-coupling [36

• previously by other groups [38][39], however, we here use a different protocol. Intermediates 25 or 26 were reacted in Suzuki–Miyaura couplings [36] with commercially available methyl 5-bromo-2-iodobenzoate [40], to obtain the key intermediate dimethyl 6,6’-(dithieno[3,2-b:2’,3’-d]thiophene-2,6-diyl)bis(3

• Information File 1. According to the literature [41], Aliquat 336® can be added to Suzuki–Miyaura reactions. Here, this did not improve the yield, but decreased its fluctuation from batch to batch. After sufficient amounts of intermediate 27 were isolated, attempts for ring-closure were made. Initial attempts

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

• organic materials, typically through Suzuki–Miyaura coupling [1][2][3][4][5][6][7]. The palladium-catalyzed boryl substitution of aryl halides with boron reagents, termed Miyaura–Ishiyama borylation, is an efficient method for synthesizing arylboronates with high functional group compatibility [8][9][10

• 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