Synthesis of acenaphthylene-fused heteroarenes and polyoxygenated benzo[j]fluoranthenes via a Pd-catalyzed Suzuki–Miyaura/C–H arylation cascade

• Merve Yence,
• Dilgam Ahmadli,
• Damla Surmeli,
• Umut Mert Karacaoğlu,
• Sujit Pal and
• Yunus Emre Türkmen

Beilstein J. Org. Chem. 2024, 20, 3290–3298, doi:10.3762/bjoc.20.273

• was selectively iodinated from the para-position with respect to the -OMe group with the use of NIS to afford iodonaphthalene 25 in 88% yield. A subsequent Miyaura borylation of 25 using B2pin2 under Pd catalysis gave boronic ester 26 in 71% yield, which set the stage for the key fluoranthene

C–C Coupling in sterically demanding porphyrin environments

• Liam Cribbin,
• Brendan Twamley,
• Nicolae Buga,
• John E. O’ Brien,
• Raphael Bühler,
• Roland A. Fischer and
• Mathias O. Senge

Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234

• substrates in their void. Keywords: C–C coupling; conformational analysis; nonplanar porphyrin; Pd-catalysis; porphyrin; Introduction Porphyrins are tetrapyrrolic macrocycles that perform essential processes in nature, such as oxygen transport in hemoglobin and photosynthesis [1]. Porphyrins are often

Synthesis and cytotoxicity studies of novel N-arylbenzo[h]quinazolin-2-amines

• Battini Veeraiah,
• Kishore Ramineni,
• Dabbugoddu Brahmaiah,
• Nangunoori Sampath Kumar,
• Hélène Solhi,
• Rémy Le Guevel,
• Chada Raji Reddy,
• Frédéric Justaud and
• René Grée

Beilstein J. Org. Chem. 2024, 20, 2592–2598, doi:10.3762/bjoc.20.218

• attractive results in this area. Keywords: Buchwald–Hartwig coupling; cytotoxicity; heterocycles; Pd catalysis; quinazolines; Introduction Nitrogen-containing heterocyclic molecules are ubiquitous in living systems. Among them, quinazolines, and especially the 4-aminoquinazolines (type A molecules, Figure

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

• substrate and participating in the key bond-forming/breaking steps via substrate–TM interactions [73][74]. This paradigm has been employed in the activation of NHPI esters under photoinduced copper (Cu) and palladium (Pd) catalysis. In 2017, Peters and Fu reported a Cu-catalyzed decarboxylative C(sp3)–N

• phthalimidyl anion would generate the aminoalkylation product 119, completing the catalytic cycle. In addition to this aminoalkylation method, the synthetic utility of radical intermediates derived from NHPI esters under photoinduced Pd-catalysis has been demonstrated in Heck-type couplings [81][82] and in the

• , whereas the corresponding spirocycle in kadsulignan E was formed under Ir photocatalysis. In addition, photoinduced Pd catalysis was applied in the key macrocyclization

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

• provides the arylpalladium intermediate 129 which after reductive elimination furnishes the desired product 127. In 2017, Chen and group [94] developed a protocol for the C2,C6-arylation of pyridine under Pd catalysis (Scheme 25). In their study, N-alkylpyridinium salts were used as a directing group

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• place slowly with 7.8% yield, meanwhile, Pd-catalysis improved the yield to 50–60% under otherwise identical conditions [50]. The approach described by the Adam’s group used H2O2 (85%) and methyltrioxorhenium(VII) (MTO) as the catalyst (Table 1, entry 5) [51][64]. Without the catalyst, the reaction

Peptide stapling by late-stage Suzuki–Miyaura cross-coupling

• Hendrik Gruß,
• Rebecca C. Feiner,
• Ridhiwan Mseya,
• David C. Schröder,
• Michał Jewgiński,
• Kristian M. Müller,
• Rafał Latajka,
• Antoine Marion and
• Norbert Sewald

Beilstein J. Org. Chem. 2022, 18, 1–12, doi:10.3762/bjoc.18.1

• 1% in proteins, but is highly conserved in binding sites on protein surfaces mediating PPI [43], it is an attractive target for the development of selective diversifications. C–H activation of the indole C2 position by Pd-catalysis allows both selective arylation [44][45][46][47][48] and formation

2,4-Bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridines: synthesis and photophysical properties

• Najeh Tka,
• Mohamed Adnene Hadj Ayed,
• Mourad Ben Braiek,
• Mahjoub Jabli,
• Noureddine Chaaben,
• Kamel Alimi,
• Stefan Jopp and
• Peter Langer

Beilstein J. Org. Chem. 2021, 17, 1629–1640, doi:10.3762/bjoc.17.115

• anthranilic acid with 2.2 equivalents of bromine in acetic acid as previously reported [64]. Subsequently, the POCl3-mediated cyclodehydration of 1 and cyclohexanone afforded 2 through an adapted reported procedure (Scheme 1) [65]. Tetrahydroacridine 2 represents a novel synthetic building block for Pd

• catalysis. With this precursor in hand, we intended to expand the π-conjugation by introducing two arylethynyl groups by Sonogashira reactions [66][67][68][69]. For the optimization, we studied the reaction of 2 with phenylacetylene (3a) and we obtained the desired product 4a in up to 72% as best yield

Methodologies for the synthesis of quaternary carbon centers via hydroalkylation of unactivated olefins: twenty years of advances

• Thiago S. Silva and
• Fernando Coelho

Beilstein J. Org. Chem. 2021, 17, 1565–1590, doi:10.3762/bjoc.17.112

• hampered the development of more general catalytic hydrofunctionalization methodologies until Widenhoefer’s work in 2001 [25]. Based on previous works that had demonstrated the addition of stabilized carbanions [26][27] and enol silyl ethers [28] to olefins under stoichiometric Pd catalysis, the authors

• further demonstrated by the hydroalkylation of the anti-inflammatory drug phenylbutazone (7j). Gold(I)/gold(III) and silver(I) catalysis in olefin hydroalkylation The early limitations associated with Pd catalysis in olefin hydroalkylation reactions prompted the search for alternative metals for olefin

Deoxyfluorination of acyl fluorides to trifluoromethyl compounds by FLUOLEAD^®/Olah’s reagent under solvent-free conditions

• Yumeng Liang,
• Akihito Taya,
• Zhengyu Zhao,
• Norimichi Saito and
• Norio Shibata

Beilstein J. Org. Chem. 2020, 16, 3052–3058, doi:10.3762/bjoc.16.254

• they only provided two examples. In 2018, Schoenebeck and co-workers reported the decarbonylative trifluoromethylation of acyl fluorides by trifluoromethyl triethylsilane (Et3SiCF3) under Pd catalysis at high temperature (Scheme 1b) [26], although the reaction was categorized as trifluoromethylation

Synthesis of 3-alkenylindoles through regioselective C–H alkenylation of indoles by a ruthenium nanocatalyst

• Abhijit Paul,
• Debnath Chatterjee,
• Srirupa Banerjee and
• Somnath Yadav

Beilstein J. Org. Chem. 2020, 16, 140–148, doi:10.3762/bjoc.16.16

• -withdrawing groups, using Pd(OAc)2 as catalyst and Cu(OAc)2 as oxidant [25]. Since then, several variants of the reaction involving Pd catalysis and various oxidants have been reported for the synthesis of 3-alkenylindoles. For example, Chen et al. and Huang et al. independently reported the C3 alkenylation

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

• and the new bond formation through reductive elimination should be less hindered, but remarkably, no reaction was observed either with the methyl ester 26b or the free acid 27b (Table 2, entries 6 and 7). Next we explored if amino-substituted silicon rhodamine 28c is accessible via Pd-catalysis. The

Switchable selectivity in Pd-catalyzed [3 + 2] annulations of γ-oxy-2-cycloalkenones with 3-oxoglutarates: C–C/C–C vs C–C/O–C bond formation

• Yang Liu,
• Julie Oble and
• Giovanni Poli

Beilstein J. Org. Chem. 2019, 15, 1107–1115, doi:10.3762/bjoc.15.107

• least in part, alleviated by performing the reaction at high temperature. However, in the specific case of this latter [bis-nucleophile/bis-electrophile] couple, the desired bicyclo[3.3.0]octane-3,7-dione structure can be better obtained under basic conditions (and in the absence of Pd catalysis), as

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

• Edorta Martínez de Marigorta,
• Jesús M. de Los Santos,
• Ana M. Ochoa de Retana,
• Javier Vicario and
• Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

• the formation of an imine by reaction of aromatic amine 2 with quinolinecarbaldehyde 97. Certainly this is a quite feasible hypothesis, since it has been reported that ortho-iodo-substituted arylimines 100, analogues of quinolinecarbaldehyde 97, also reacted, under Pd catalysis, with CO (23) and

Heterogeneous Pd catalysts as emulsifiers in Pickering emulsions for integrated multistep synthesis in flow chemistry

• Katharina Hiebler,
• Georg J. Lichtenegger,
• Manuel C. Maier,
• Eun Sung Park,
• Renie Gonzales-Groom,
• Bernard P. Binks and
• Heidrun Gruber-Woelfler

Beilstein J. Org. Chem. 2018, 14, 648–658, doi:10.3762/bjoc.14.52

• . Keywords: compartmentalisation; heterogeneous catalysis; multistep flow chemistry; palladium; Pickering emulsions; Introduction Palladium (Pd) catalysis has been established as a key component in the toolbox of organic chemists. Reactions that are catalysed by palladium benefit from the remarkable

• and lifetime. Apart from that, ligand-free Pd catalysts are also known in the literature [11][12]. However, homogeneous Pd catalysis often requires catalyst loadings in the order of mol % to achieve effective coupling and suffers from catalyst re-use and recycling problems [11][13]. Furthermore

Nitration of 5,11-dihydroindolo[3,2-b]carbazoles and synthetic applications of their nitro-substituted derivatives

• Roman A. Irgashev,
• Nikita A. Kazin,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2017, 13, 1396–1406, doi:10.3762/bjoc.13.136

• performed by using the Suzuki–Miyaura cross-coupling reaction with phenylboronic acid under Pd catalysis (Scheme 5). The location of the formyl group and bromine atoms in ICZ derivatives 12 and 13 has been established by X-ray crystallography analysis, performed for single crystals of 12b and 13b (Figure 5

Pd- and Cu-catalyzed approaches in the syntheses of new cholane aminoanthraquinone pincer-like ligands

• Nikolay V. Lukashev,
• Gennadii A. Grabovyi,
• Dmitry A. Erzunov,
• Alexey V. Kazantsev,
• Gennadij V. Latyshev,
• Alexei D. Averin and
• Irina P. Beletskaya.

Beilstein J. Org. Chem. 2017, 13, 564–570, doi:10.3762/bjoc.13.55

• arylation of aminocholanes has been described for the first time. While this Cu-catalyzed protocol provides high yields in reactions of aminocholanes with iodoarenes, Pd catalysis was found to be preferable for the reactions of aminocholanes with dichloroanthraquinones. UV–vis titration of bis(cholanylamino

• )anthraquinones with a series of cations demonstrated their high binding affinity to Cu2+, Al3+, and Cr3+. Keywords: amination; aminocholanes; bile acids; cation complexation; Cu-catalysis; diaminoanthraquinone; Pd-catalysis; Introduction Bile acids are known to ensure vital processes in vertebrate organisms

Et₃B-mediated and palladium-catalyzed direct allylation of β-dicarbonyl compounds with Morita–Baylis–Hillman alcohols

• Ahlem Abidi,
• Yosra Oueslati and
• Farhat Rezgui

Beilstein J. Org. Chem. 2016, 12, 2402–2409, doi:10.3762/bjoc.12.234

• formation of only water as a side product. This method provides a straightforward and practical route to a range of allylated compounds. Further work is in progress in our laboratory to investigate the Pd catalysis of the reaction of the MBH adducts with various pronucleophiles including nitroalkanes

Further exploration of the heterocyclic diversity accessible from the allylation chemistry of indigo

• Alireza Shakoori,
• John B. Bremner,
• Mohammed K. Abdel-Hamid,
• Anthony C. Willis,
• Rachada Haritakun and
• Paul A. Keller

Beilstein J. Org. Chem. 2015, 11, 481–492, doi:10.3762/bjoc.11.54

• of 2-allyloxyindoles by related Pd catalysis have been reported [14]. The 13C NMR spectrum of 31 showed only one set of peaks for the molecule indicating that only one pair of enantiomers was present, despite the presence of three stereogenic atoms. This is likely to arise from the spiro starting

An unusually stable chlorophosphite: What makes BIFOP–Cl so robust against hydrolysis?

• Roberto Blanco Trillo,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2015, 11, 313–322, doi:10.3762/bjoc.11.36

• application as a chiral ligand to be used in, for example, Pd catalysis [13][14][15]. Experimental All reactions were carried out under an inert argon atmosphere and in heated glassware using standard Schlenk techniques. Anhydrous solvents were obtained by distillation from sodium benzophenone ketyl. The NMR

P(O)R₂-directed Pd-catalyzed C–H functionalization of biaryl derivatives to synthesize chiral phosphorous ligands

• Rong-Bin Hu,
• Hong-Li Wang,
• Hong-Yu Zhang,
• Heng Zhang,
• Yan-Na Ma and
• Shang-dong Yang

Beilstein J. Org. Chem. 2014, 10, 2071–2076, doi:10.3762/bjoc.10.215

• products are produced with good enantioselectivity. Keywords: chiral synthesis; Pd-catalysis; organophosphorus; phosphorus ligands; P(O)R2-directing; Introduction In the past decades, phosphorus ligands have been demonstrated to be efficient ligands in many metal-catalyzed organic reactions [1][2][3][4

Facile synthesis of 1-alkoxy-1H-benzo- and 7-azabenzotriazoles from peptide coupling agents, mechanistic studies, and synthetic applications

• Mahesh K. Lakshman,
• Manish K. Singh,
• Mukesh Kumar,
• Raghu Ram Chamala,
• Vijayender R. Yedulla,
• Domenick Wagner,
• Evan Leung,
• Lijia Yang,
• Asha Matin and
• Sadia Ahmad

Beilstein J. Org. Chem. 2014, 10, 1919–1932, doi:10.3762/bjoc.10.200

• ][1,2,3]triazole, via in situ formation of pyrrolidine enamines and Pd catalysis. Keywords: alkoxy; azabenzotriazole; benzotriazole; peptide-coupling; phosphonium; Introduction Benzotriazole derivatives are of importance in diverse contexts. As examples, in medicinal chemistry substituted benzotriazoles

Stereoselective synthesis of carbocyclic analogues of the nucleoside Q precursor (PreQ₀)

• Sabin Llona-Minguez and
• Simon P. Mackay

Beilstein J. Org. Chem. 2014, 10, 1333–1338, doi:10.3762/bjoc.10.135

• introduction of diverse aryl groups at the 3-position of the cyclohexane ring using commercially available arylboronic acids as building blocks, and Pd catalysis to form the new C–C bond, followed by a highly diastereoselective ketone-to-amine conversion. Others have reported on similar preparations of 3

Gold-catalyzed regioselective oxidation of propargylic carboxylates: a reliable access to α-carboxy-α,β-unsaturated ketones/aldehydes

• Kegong Ji,
• Jonathan Nelson and
• Liming Zhang

Beilstein J. Org. Chem. 2013, 9, 1925–1930, doi:10.3762/bjoc.9.227

• polarization of the C–C triple bond by the propargylic BnO group. The better result with 4i also containing a similarly positioned BnO group (entry 8) is attributed to the synergistic effect of the steric bias [2]. While a previous Pd catalysis [43] could also accomplish this transformation, the demonstrated

Efficient Cu-catalyzed base-free C–S coupling under conventional and microwave heating. A simple access to S-heterocycles and sulfides

• Silvia M. Soria-Castro and
• Alicia B. Peñéñory

Beilstein J. Org. Chem. 2013, 9, 467–475, doi:10.3762/bjoc.9.50

• ), this Cu-catalyzed C–S coupling reaction being highly chemoselective for aryl iodides. In comparison with the already reported procedure for the preparation of S-aryl thioacetates by Pd catalysis [51][56], the methodology herein described has the advantages of using a lower-cost copper salt and a stable