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

Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition

• Sivaraman Balasubramaniam,
• Sajith Vijayan,
• Liam V. Goldman,
• Xavier A. May,
• Kyra Dodson,
• Sweta Adhikari,
• Fatima Rivas,
• Davita L. Watkins and
• Shana V. Stoddard

Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59

• performed a Suzuki coupling reaction between boronic acid 15 with chloro compound 2 (Scheme 2). To the best of our knowledge, there is no report of a Suzuki coupling reaction using boronic acid 15 in the literature. However, we generated this required boronic acid from the corresponding methyl propiolate

• Information File 1, Figure S7) and δ 6.57 and 7.63 ppm with a J value of 15 Hz for compound 18 (Supporting Information File 1, Figure S9) as inferred by 1H NMR analysis. The resulting Suzuki-coupled products 16 and 18, were subjected to benzylic oxidation expecting the olefin functionality would facilitate

• literature procedure [39]. The intermediate 21 was then subjected to the Suzuki reaction using conditions already developed to provide the ester aldehyde 17 in overall yield of 16% for two steps. Having identified synthetically suitable conditions for compound 17, we scaled up the reaction to complete the

Direct borylation of terrylene and quaterrylene

• Haruka Kano,
• Keiji Uehara,
• Kyohei Matsuo,
• Hironobu Hayashi,
• Hiroko Yamada and
• Naoki Aratani

Beilstein J. Org. Chem. 2020, 16, 621–627, doi:10.3762/bjoc.16.58

• hinderance of Bpin moieties. Finally, to demonstrate the utility of the borylated oligorylenes, the Suzuki–Miyaura cross-coupling reaction of TB4 under the standard conditions was performed (Scheme 3). Coupling of TB4 and 2-bromomesitylene with Pd(PPh3)4, Cs2CO3 and CsF in a mixture of toluene/DMF furnished

• -dioxaborolan-2-yl. Synthesis of 2,5,12,15-tetrakis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)quaterrylene (QB4): (a) (Bpin)2 (12 equiv), [Ir(OMe)cod]2 (20 mol %), di-tert-butylbipyridyl (40 mol %), 1,4-dioxane, at 105 °C, 38 h, yield 0.4%. Suzuki–Miyaura cross-coupling reaction of TB4 with 2-bromomesitylene

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

• /mechanical stability, and good adsorption capacity. They also contain an ordered porous network that is appropriate for the free diffusion of reactants and reaction products [24]. In this regard, various functionalized SiO2 nanoparticles were employed in diverse organic reactions, including Suzuki–Miyaura

• employed in diverse organic reactions, including Suzuki reactions [64], Sonogashira reactions [65], transesterifications of triglycerides [66], hydrogenation reactions [67], N-heterocycle syntheses [68], cleavage of propargyl phenol ethers [69], etc. [70][71][72][73][74][75]. In this review article, we

• delivery [93], and cancer detection [94]. In this regard, various functionalized MNPs were employed in diverse organic reactions, including Suzuki–Miyaura reactions, Sonogashira reactions, Ullmann coupling, hydrogenation reactions, oxidation reactions, hydroformylation reactions, and “click” reactions [89

Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[a,d,j,m]coronenes by selective C–H/C–O arylations of anthraquinone derivatives

• Seiya Terai,
• Yuki Sato,
• Takuya Kochi and
• Fumitoshi Kakiuchi

Beilstein J. Org. Chem. 2020, 16, 544–550, doi:10.3762/bjoc.16.51

• reaction, followed by dehydrogenative photocyclization, and FeCl3-mediated oxidative cyclization (Scheme 2a) [43]. Tao, Chao, and co-workers succeeded in the preparation of similar tetrasubstituted tetrabenzocoronenes by a Corey–Fuchs reaction, followed by a Suzuki–Miyaura cross-coupling, and a two-step

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

• molecules, thus having drawn much attention. Transition metal-catalyzed C–X/C–M cross-coupling reactions such as Suzuki and Stille couplings are the main approaches to achieve the arylation of PAHs [7][8][9][10][11]. However, the selective arylation of the C7-position of 1-naphthoic acid derivatives remains

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

• via 1,4-cobalt migration. The resulting 7-hydroxybenzo[b]phosphole derivative was used for further π-extension through Suzuki–Miyaura couplings and a Scholl reaction, the latter closing the triphenylene ring. The absorption and emission spectra of the thus-synthesized compounds illustrated their

• π-extension through a Suzuki–Miyaura coupling, Sonogashira coupling, and electrophilic alkyne carbocyclization [18]. Given the successful synthesis of the angularly fused phosphahelicenes, we became interested in the further exploitation of 7-hydroxybenzo[b]phosphole as an intermediate for the

• converted to the triflate, and subjected to Suzuki–Miyaura couplings with 2-bromophenylboronic acid (5a) or 3-bromonaphth-2-ylboronic acid (5b) to afford the phosphole-fused biaryls 6a and 6b, respectively, in decent yields. Subsequent Suzuki–Miyaura couplings of 6a or 6b with 3,4-dialkoxyarylboronic acids

Formal preparation of regioregular and alternating thiophene–thiophene copolymers bearing different substituents

• Atsunori Mori,
• Keisuke Fujita,
• Chihiro Kubota,
• Toyoko Suzuki,
• Kentaro Okano,
• Takuya Matsumoto,
• Takashi Nishino and
• Masaki Horie

Beilstein J. Org. Chem. 2020, 16, 317–324, doi:10.3762/bjoc.16.31

• Atsunori Mori Keisuke Fujita Chihiro Kubota Toyoko Suzuki Kentaro Okano Takuya Matsumoto Takashi Nishino Masaki Horie Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan Research Center for Membrane and Film Technology, Kobe University, 1-1

Synthesis of 4-(2-fluorophenyl)-7-methoxycoumarin: experimental and computational evidence for intramolecular and intermolecular C–F···H–C bonds

• Vuyisa Mzozoyana,
• Fanie R. van Heerden and
• Craig Grimmer

Beilstein J. Org. Chem. 2020, 16, 190–199, doi:10.3762/bjoc.16.22

• , numerous methods for the synthesis of these compounds have been developed, examples are the Pechmann condensation [10][11], Stille coupling reaction [12], Knoevenagel condensation [13], Heck coupling reaction [14], Kostanecki reaction, Baylis–Hillman reaction [15], Michael reaction [16], Suzuki–Miyaura

Synthesis and optoelectronic properties of benzoquinone-based donor–acceptor compounds

• Daniel R. Sutherland,
• Nidhi Sharma,
• Georgina M. Rosair,
• Ifor D. W. Samuel,
• Ai-Lan Lee and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2019, 15, 2914–2921, doi:10.3762/bjoc.15.285

• difunctionalization is dependent on the electronics of the substituent added to BQ) [14], 5 was instead furnished from the dibromo-functionalized BQ 1-Br2 using a double Suzuki coupling. As expected, much harsher conditions (100 °C) were required to achieve conversions under Pd(0) catalysis to produce 5 in 22% yield

• consistent with 3 having higher ΦPL than the other compounds. Conclusion Three novel monofunctionalized donor–acceptor BQ derivatives 2–4 were synthesized using an efficient Pd-catalyzed C–H functionalization method, and novel 2,5-difunctionalized BQ derivative 5 was also obtained via Suzuki coupling. The

• monofunctionalization of BQ (1). Synthesis of 5 via double Suzuki coupling. Electrochemical properties of 2–5. Optoelectronic properties of 2–5. Supporting Information The research data supporting this publication can be accessed at https://doi.org/10.17630/178f3a7c-4717-43f0-a145-049675825e1a. Supporting Information

Palladium-catalyzed synthesis and nucleotide pyrophosphatase inhibition of benzo[4,5]furo[3,2-b]indoles

• Hoang Huy Do,
• Saif Ullah,
• Alexander Villinger,
• Joanna Lecka,
• Jean Sévigny,
• Peter Ehlers,
• Jamshed Iqbal and
• Peter Langer

Beilstein J. Org. Chem. 2019, 15, 2830–2839, doi:10.3762/bjoc.15.276

• , Québec, QC, G1V 4G2, Canada Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert Einstein Str. 29a, 18059 Rostock, Germany 10.3762/bjoc.15.276 Abstract A two-step palladium-catalyzed procedure based on Suzuki–Miyaura cross coupling, followed by a double Buchwald–Hartwig reaction, allows

• results were rationalized based on docking studies. Keywords: Buchwald–Hartwig reaction; cyclization; N-heterocycles; palladium; Suzuki–Miyaura reaction; Introduction Furoindoles and their derivatives have received a lot of attention based on their versatile pharmaceutical activities. Furoindols were

• diindolofurans by regioselective Suzuki–Miyaura couplings of tetrabromofuran and subsequent cyclization by tetrafold Buchwald–Hartwig reaction [31]. We also studied the synthesis of benzo[4,5]furo[3,2-b]indoles by a similar concept. However, while performing our studies, Truong et al. reported the synthesis of

An improved, scalable synthesis of Notum inhibitor LP-922056 using 1-chloro-1,2-benziodoxol-3-one as a superior electrophilic chlorinating agent

• Nicky J. Willis,
• Elliott D. Bayle,
• George Papageorgiou,
• David Steadman,
• Benjamin N. Atkinson,
• William Mahy and
• Paul V. Fish

Beilstein J. Org. Chem. 2019, 15, 2790–2797, doi:10.3762/bjoc.15.271

• biology of Notum and build target validation to underpin new drug discovery programs. Results: An improved, scalable synthesis of 1 is reported. Key modifications include: (1) the introduction of the C7-cyclopropyl group was most effectively achieved with a Suzuki–Miyaura cross-coupling reaction with MIDA

• group was most effectively achieved with a Suzuki–Miyaura cross-coupling reaction with MIDA-boronate 11 (5 → 6); and (2) C6 chlorination was performed with 1-chloro-1,2-benziodoxol-3-one (12) (6 → 7) as a mild selective electrophilic chlorination agent. 4-Chlorothieno[3,2-d]pyrimidine (3) was either

• efficient step in our sequence and justified further optimisation (vide infra). Suzuki–Miyaura cross coupling of bromide 5 with cyclopropylboronic acid (2.5 equiv) produced 6 in good yield (62–89%) but the product required extensive chromatographic purification. We reasoned that switching from the boronic

A chiral self-sorting photoresponsive coordination cage based on overcrowded alkenes

• Constantin Stuckhardt,
• Diederik Roke,
• Wojciech Danowski,
• Edwin Otten,
• Sander J. Wezenberg and
• Ben L. Feringa

Beilstein J. Org. Chem. 2019, 15, 2767–2773, doi:10.3762/bjoc.15.268

• formed revealing that a chiral self-sorting process takes place. In addition, two of the cage isomers can bind a tosylate anion in solution by formation of a host–guest complex. Results and Discussion Ligands Z-1 and E-1 (Scheme 1) were synthesized by a Suzuki cross-coupling reaction of 3

Progress in metathesis chemistry

• Karol Grela and
• Anna Kajetanowicz

Beilstein J. Org. Chem. 2019, 15, 2765–2766, doi:10.3762/bjoc.15.267

• catalysts work and decompose, how macrocycles are formed in ring-closing metathesis, etc. Representative examples of these directions have been the subject of the current, third thematic issue on Olefin Metathesis, including highly educative reviews on tandem olefin metathesis–Suzuki–Miyaura cross coupling

Acid-catalyzed rearrangements in arenes: interconversions in the quaterphenyl series

• Sarah L. Skraba-Joiner,
• Carter J. Holt and
• Richard P. Johnson

Beilstein J. Org. Chem. 2019, 15, 2655–2663, doi:10.3762/bjoc.15.258

• , samples of m,p’- (13), o,p’- (15), o,m’- (16), and o,o’-quaterphenyl (17) were synthesized as shown in Scheme 3. Suzuki–Miyaura coupling was used to synthesize 13, 15, and 16 from the corresponding aryl bromides and boronic acids [35]. o,o’-Quaterphenyl (17) was synthesized by homo-coupling of 2

• through time-of-flight matrix assisted laser desorption ionization (MALDI–TOF–MS) mass spectrometry, using sulfur as a matrix. Suzuki–Miyaura coupling to form m,p’-quaterphenyl (13) [35]: 4-Biphenylboronic acid (0.18 g, 0.91 mmol) and 1 M K2CO3 (1.5 mL) were added to a 10 mL Pyrex microwave tube. 3

• (400 MHz, CDCl3) δ 7.87–7.85 (m, 1H), 7.76–7.69 (m, 4H), 7.69–7.64 (m, 4H), 7.64–7.58 (m, 2H), 7.57–7.52 (m, 1H), 7.50–7.45 (m, 4H), 7.41–7.35 (m, 2H). Suzuki–Miyaura coupling to form o,p’-quaterphenyl (15) [35]: K2CO3 (0.91 g, 6.6 mmol) and water (7.7 mL) were combined in a 25 mL round bottom flask

Arylisoquinoline-derived organoboron dyes with a triaryl skeleton show dual fluorescence

• Vânia F. Pais,
• Tristan Neumann,
• Ignacio Vayá,
• M. Consuelo Jiménez,
• Abel Ros and
• Uwe Pischel

Beilstein J. Org. Chem. 2019, 15, 2612–2622, doi:10.3762/bjoc.15.254

• , 41012 Seville, Spain 10.3762/bjoc.15.254 Abstract Four new dyes that derive from borylated arylisoquinolines were prepared, containing a third aryl residue (naphthyl, 4-methoxynaphthyl, pyrenyl or anthryl) that is linked via an additional stereogenic axis. The triaryl cores were synthesized by Suzuki

• -coupling reactions was planned. Starting from 1-bromo-4-methoxynaphthalene (1), the Pd-catalyzed Suzuki coupling reaction with commercial boronic acids afforded the naphthyl and pyrenyl derived methyl ethers 2 and 3 in 78% and 87% yield, respectively (Scheme 1). For the synthesis of the anthryl derivative

• 5 a Pd-catalyzed one-pot reaction consisting of a borylation and Suzuki coupling was applied. Thus, starting from 1-chloroanthracene (4) and using SPhos/Pd2dba3 (8:1) as the catalyst, a full conversion to the Miyaura-type borylated intermediate was achieved (TLC analysis) after 5 hours at 110 ºC

A new approach to silicon rhodamines by Suzuki–Miyaura coupling – scope and limitations

• Thines Kanagasundaram,
• Antje Timmermann,
• Carsten S. Kramer and
• Klaus Kopka

Beilstein J. Org. Chem. 2019, 15, 2569–2576, doi:10.3762/bjoc.15.250

• application in STED (stimulated emission depletion) microscopy, as sensor molecules for, e.g., ions and as fluorophores for the optical imaging of tumors. Different strategies were already employed for their synthesis. Because of just three known literature examples in which Suzuki–Miyaura cross couplings

• functionalized with free acid moieties are directly accessible in contrast to previously described methods. Keywords: cross coupling; fluorescent dyes; near-infrared (NIR) dyes; silicon rhodamines; Suzuki–Miyaura coupling; Introduction Silicon rhodamines are versatile fluorescent dyes that found extensive use

• 53–79% were obtained (for O and S analogues; 85–99% yields based on recovered starting material (brsm)). Since the yields reported by Urano for the Si-analogous Suzuki reactions were much lower (6–23%) [22], we wanted to examine if the aforementioned substrates were outliers and a cross-coupling

Self-assembled coordination thioether silver(I) macrocyclic complexes for homogeneous catalysis

• Zhen Cao,
• Aline Lacoudre,
• Cybille Rossy and
• Brigitte Bibal

Beilstein J. Org. Chem. 2019, 15, 2465–2472, doi:10.3762/bjoc.15.239

• reactions of alkynes. Results and Discussion Synthesis of silver(I) complexes Ligand 1 was synthesized in one step, from commercially available 9,10-dibromoanthracene and 2-(methylthio)phenylboronic acid, using a Suzuki–Miyaura cross-coupling reaction. Notably, the yield was low (26%) [55], and the X-ray

Targeted photoswitchable imaging of intracellular glutathione by a photochromic glycosheet sensor

• Xianzhi Chai,
• Hai-Hao Han,
• Yi Zang,
• Jia Li,
• Xiao-Peng He,
• Junji Zhang and
• He Tian

Beilstein J. Org. Chem. 2019, 15, 2380–2389, doi:10.3762/bjoc.15.230

• synthesis of dithienylethene fluorescence reporter Glyco-DTE is shown in Scheme 2. The dithienylethene derivative 3 was prepared by Suzuki coupling of dithienylethene 1 with methyl 4-bromobenzoate followed by hydrolysis with lithium hydroxide. The naphthalimide fluorophore 6 was synthesized through bromide

Mono- and bithiophene-substituted diarylethene photoswitches with emissive open or closed forms

• A. Lennart Schleper,
• Mariano L. Bossi,
• Vladimir N. Belov and
• Stefan W. Hell

Beilstein J. Org. Chem. 2019, 15, 2344–2354, doi:10.3762/bjoc.15.227

• regioisomeric bromides were also formed, but they were separated by column chromatography on the next step. Bithiophene 11 was prepared in 74% yield by using a Suzuki–Miyaura coupling (catalyzed by PEPPSI-IPr) between boronic ester 9 and bromide 10 [13][14]. Boronation of bithiophene 11 was achieved under

• , AsOTh2, and SyOTh2 (Figure 1) were obtained using a standard procedure for a Suzuki–Miyaura coupling of iodides 4, 5, 7, and 8 with boronic acid esters 9 and 12 (see Scheme 3). Throughout the text, abbreviations “As” and “Sy” denote asymmetric and symmetric substitution patterns, respectively; “O

• esters 9 and 12 (bpy – 4,4’-di-tert-butyl-2,2’-dipyridine; COD – cycloocta-1,5-diene; NBS – N-bromosuccinimide, DCM – dichloromethane). Photoswitchable diarylethenes AsTh1, SyTh1, AsTh2, SyTh2, AsOTh1, SyOTh1, AsOTh2, and SyOTh2 synthesized via a Suzuki–Miyaura coupling. Conditions: 60 °C, argon

Functionalization of 4-bromobenzo[c][2,7]naphthyridine via regioselective direct ring metalation. A novel approach to analogues of pyridoacridine alkaloids

• Benedikt C. Melzer,
• Alois Plodek and
• Franz Bracher

Beilstein J. Org. Chem. 2019, 15, 2304–2310, doi:10.3762/bjoc.15.222

• , phenolates), acyl anions (generated by umpolung of aldehydes with imidazolium salts) and by palladium-catalyzed cross-coupling reactions (Suzuki, Stille) [10]. A related Stille cross coupling of a benzo[c][2,7]naphthyridine bearing a triflate group at C-5 gave an intermediate for the total synthesis of

• , which undergo rearomatization as described above (Figure 2B). 4-Bromo-5-(methoxycarbonyl)benzo[c][2,7]naphthyridine generated this way gave, after Suzuki cross-coupling at C-4, intermediates for the synthesis of analogues of ascididemin (2) [16]. Introduction of (hetero)aromatic rings bearing ester

• groups in ortho-position into 4-bromobenzo[c][2,7]naphthyridine (9d) under Suzuki or Negishi conditions gave 4-aryl derivatives 10 which underwent cyclization to pyridoacridones through directed remote ring metalation at C-5, followed by spontaneous intramolecular trapping of the ester group [17][18

Azologization and repurposing of a hetero-stilbene-based kinase inhibitor: towards the design of photoswitchable sirtuin inhibitors

• Christoph W. Grathwol,
• Nathalie Wössner,
• Sören Swyter,
• Adam C. Smith,
• Enrico Tapavicza,
• Robert K. Hofstetter,
• Anja Bodtke,
• Manfred Jung and
• Andreas Link

Beilstein J. Org. Chem. 2019, 15, 2170–2183, doi:10.3762/bjoc.15.214

• -bromonicotinate (3b). If 3b was used, transformation to the nicotinamide was accomplished almost quantitatively by addition of a saturated solution of ammonia in anhydrous methanol and stirring in a closed vessel at 40 °C. Compounds 4a and b could easily be obtained through Suzuki coupling with commercially

• ) as alkene component had detrimental effects on the yields in the synthesis of 2d, 2f and 2h. Intermediates 5a and 5b were accessible from 3a and 3b via Suzuki–Miyaura or Stille coupling [34]. Biology The influence on deacetylase activity of three human sirtuin isoforms (Sirt1–3) was determined in a

Norbornadiene-functionalized triazatriangulenium and trioxatriangulenium platforms

• Roland Löw,
• Talina Rusch,
• Tobias Moje,
• Fynn Röhricht,
• Olaf M. Magnussen and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1815–1821, doi:10.3762/bjoc.15.175

• obtained in a convergent synthesis (Scheme 2). Boronic ester 9 was synthesized as described in the literature [15]. In a Suzuki cross-coupling reaction norbornadiene 4 was coupled with 9 to the extended norbornadiene 10 (38%), which was attached to the TATA platform 6 to yield the extended norbornadiene

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

• -catalyzed cross-coupling reactions have laid down the foundation of new C–C bond formations [50][51]. A number of Pd-catalyzed organic reactions viz., C–N coupling, amination and intramolecular amidation, cyclization, and Suzuki–Miyaura coupling [52][53][54][55] have recently been reported in the literature

• Suzuki, Sonogashira and Heck coupling reactions (Scheme 48). The reaction proceeded by the formation of 1-iodoalkyne 142 which was characterized by mass and 1H NMR spetra. This iodoalkyne then formed a complex of Cu(I) with 2-AP. This was followed by migratory insertion of haloalkyne to form reactive Cu

Synthesis of pyrrolo[1,2-a]quinolines by formal 1,3-dipolar cycloaddition reactions of quinolinium salts

• Anthony Choi,
• Rebecca M. Morley and
• Iain Coldham

Beilstein J. Org. Chem. 2019, 15, 1480–1484, doi:10.3762/bjoc.15.149

• could be converted to other derivatives by Suzuki–Miyaura coupling, reduction or oxidation reactions. Keywords: azomethine ylide; cycloaddition; heterocycle; pyrrolidine; stereoselective; Introduction Cycloaddition reactions of azomethine ylides are an important class of pericyclic reactions that give

• ). The adducts could be reduced, oxidised, or could undergo Suzuki–Miyaura coupling to give different substituted dihydro- and tetrahydroquinoline derivatives. Single crystal X-ray structure for 7c. Single crystal X-ray structure for 9. Reaction of ketone 1 with electron-deficient alkenes 2. Reactions of

• ester 4 and amide 5 with electron-deficient alkenes 6. Reactions of ester 4 and amide 5 with N-methylmaleimide. Reduction and oxidation of adducts 9 and 10. Formation of amides 15a and 15b and Suzuki–Miyaura coupling to yield 16. Supporting Information Supporting Information File 322: Experimental