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

Total synthesis of elansolids B1 and B2

• Liang-Liang Wang and
• Andreas Kirschning

Beilstein J. Org. Chem. 2017, 13, 1280–1287, doi:10.3762/bjoc.13.124

• an optimized C–C cross-coupling sequence with a Suzuki cross-coupling reaction as key step. Keywords: antibiotics; polyenes; polyketides; Stille reaction; Suzuki reaction; total synthesis; Introduction The elansolids are metabolites from the gliding bacterium Chitinophaga sancti (formerly

• . Results and Discussion The improved synthesis utilizes the Suzuki–Miyaura cross-coupling reaction to merge the western fragment derived from ketone 9 with the newly designed eastern building block 13. This fragment was obtained in very good yield from vinyl iodide 12 [9] by a Stille protocol using doubly

• )-configured triene units are ideally be constructed, clearly demonstrating that enediynes are less preferred precursors for such structural elements. It has to be noted that there is precedence in the literature for the use of the Suzuki–Miyaura cross-coupling reaction as key step to assemble differently

Aggregation behaviour of a single-chain, phenylene-modified bolalipid and its miscibility with classical phospholipids

• Simon Drescher,
• Vasil M. Garamus,
• Christopher J. Garvey,
• Annette Meister and
• Alfred Blume

Beilstein J. Org. Chem. 2017, 13, 995–1007, doi:10.3762/bjoc.13.99

• -Mothes-Str. 3, 06120 Halle (Saale), Germany 10.3762/bjoc.13.99 Abstract In the present work, we describe the synthesis of a single-chain, phenylene-modified bolalipid with two phosphocholine headgroups, PC-C18pPhC18-PC, using a Sonogashira cross-coupling reaction as a key step. The aggregation behaviour

• synthesised from the corresponding diol (HO-C18pPhC18-OH) by established phosphorylation and quarternisation reactions described previously [38]. The long-chain, phenylene-modified 1,ω-diol in turn was prepared using a bis-Sonogashira cross-coupling reaction [37] with PdCl2(PPh3)2 as catalyst and tetra-n

A strategic approach to [6,6]-bicyclic lactones: application towards the CD fragment of DHβE

• Tue Heesgaard Jepsen,
• Emil Glibstrup,
• François Crestey,
• Anders A. Jensen and
• Jesper Langgaard Kristensen

Beilstein J. Org. Chem. 2017, 13, 988–994, doi:10.3762/bjoc.13.98

• effective synthetic protocol to access [6,6]-bicyclic lactone moieties through a regio- and stereoselective intramolecular Mizoroki–Heck cross-coupling reaction followed by a 6π-electrocyclization. This method enabled the first synthesis of the elusive CD fragment of the Erythrina alkaloid DHβE. Preliminary

• pharmacological evaluations support the notion that the key pharmacophores of DHβE are located in the A and B rings. Keywords: DhβE; Mizoroki–Heck cross-coupling reaction; 6π-electrocyclization; [6,6]-bicyclic lactone; vinyl halide; Introduction The neuronal nicotinic acetylcholine receptors (nAChRs) have been

• intramolecular Mizoroki–Heck cross-coupling reaction and a 6π-electrocyclization as key steps. Results and Discussion First strategy with Ts and Cbz protecting groups As depicted in Scheme 1, our first strategy featured a late stage installation of the lactonic D ring by a 6π-electrocyclization and formation of

Synthesis of tetrasubstituted pyrazoles containing pyridinyl substituents

• Josef Jansa,
• Ramona Schmidt,
• Ashenafi Damtew Mamuye,
• Laura Castoldi,
• Alexander Roller,
• Vittorio Pace and
• Wolfgang Holzer

Beilstein J. Org. Chem. 2017, 13, 895–902, doi:10.3762/bjoc.13.90

• -coupling reaction with organozinc compounds [23][24] is a valuable tool for the formation of C–C bonds, particularly in the presence of functional groups. The employed organozinc reagents are relatively reactive nucleophiles undergoing rapid transmetalation with appropriate transition metal species, for

• the main product, but also containing biphenyl, traces of the desired product 6a, the homocoupling dimer 7a as well as a compound 8, obviously resulting from attack of PhLi to the pyridine system attached to pyrazole N-1 (Scheme 4). Negishi cross-couplings with 4-iodopyrazoles 3a–d The Negishi cross

Nucleophilic and electrophilic cyclization of N-alkyne-substituted pyrrole derivatives: Synthesis of pyrrolopyrazinone, pyrrolotriazinone, and pyrrolooxazinone moieties

• Işıl Yenice,
• Sinan Basceken and
• Metin Balci

Beilstein J. Org. Chem. 2017, 13, 825–834, doi:10.3762/bjoc.13.83

• by a copper-catalyzed cross-coupling reaction. Nucleophilic cyclization of N-alkyne-substituted methyl 1H-pyrrole-2-carboxylates with hydrazine afforded the 6-exo-dig/6-endo-dig cyclization products depending on the electronic nature of the substituents attached to the alkyne. On the other hand

A practical and efficient approach to imidazo[1,2-a]pyridine-fused isoquinolines through the post-GBB transformation strategy

• Taofeng Shao,
• Zhiming Gong,
• Tianyi Su,
• Wei Hao and
• Chao Che

Beilstein J. Org. Chem. 2017, 13, 817–824, doi:10.3762/bjoc.13.82

• tolerated the reaction conditions, allowing for the further manipulation through various cross-coupling reaction (Table 2, entry 9). Conclusion In conclusion, we have developed a practical and efficient synthetic approach to structurally diverse imidazo[1,2-a]pyridine-fused isoquinolines with moderate to

Efficient access to β-vinylporphyrin derivatives via palladium cross coupling of β-bromoporphyrins with N-tosylhydrazones

• Vinicius R. Campos,
• Ana T. P. C. Gomes,
• Anna C. Cunha,
• Maria da Graça P. M. S. Neves,
• Vitor F. Ferreira and
• José A. S. Cavaleiro

Beilstein J. Org. Chem. 2017, 13, 195–202, doi:10.3762/bjoc.13.22

• , 3810-193 Aveiro, Portugal 10.3762/bjoc.13.22 Abstract This work describes a new approach to obtain new β-vinylporphyrin derivatives through palladium-catalyzed cross-coupling reaction of 2-bromo-5,10,15,20-tetraphenylporphyrinatozinc(II) with N-tosylhydrazones. This is the first report of the use of

• decided to explore the palladium-catalyzed cross-coupling reaction of meso-tetraphenyl-β-bromoporphyrin using N-tosylhydrazone derivatives with different electronic features for the preparation of new β-alkenyl-type porphyrin derivatives. This approach can provide interesting compounds with potential

• the authors reported an efficient methodology for the palladium-catalyzed cross-coupling reaction of electron-deficient aryl halides with aryl N-tosylhydrazones. In such a way, under these new conditions, the reactions between β-bromonated porphyrin 1 and N-tosylhydrazone derivatives 2a–c were

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

• Michal Medvecký,
• Igor Linder,
• Luise Schefzig,
• Hans-Ulrich Reissig and
• Reinhold Zimmer

Beilstein J. Org. Chem. 2016, 12, 2898–2905, doi:10.3762/bjoc.12.289

• . Cross-coupling reaction of 1,2-oxazine anti-4d leading to 5-cyano-substituted 1,2-oxazine anti-25. Desilylation of 1,2-oxazine syn-5 and subsequent click reaction with benzyl azide leading to 5-(1,2,3-triazolyl)-substituted 1,2-oxazine syn-26. Hydrogenation of 1,2-oxazine syn-21 leading to γ-amino

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications

• Desta Gedefaw,
• Marta Tessarolo,
• Margherita Bolognesi,
• Mario Prosa,
• Renee Kroon,
• Wenliu Zhuang,
• Patrik Henriksson,
• Kim Bini,
• Ergang Wang,
• Michele Muccini,
• Mirko Seri and
• Mats R. Andersson

Beilstein J. Org. Chem. 2016, 12, 1629–1637, doi:10.3762/bjoc.12.160

•  1 shows the synthesis of the two polymers. The BDT (1 and 2) and Tz (3) based monomers were synthesized following literature procedures [21][22]. Thus, Stille cross-coupling reaction between the BDT and Tz based monomers gave the desired polymers in excellent yield. The molecular weights of the

• /PTzBDT-2:PC61BM based devices. AFM images (size: 5 µm × 5 µm) of: A) 1:2 (wt/wt) PTzBDT-1:PC61BM (RMS of ~1.5 nm) and, B) 1:1 (wt/wt) PTzBDT-2:PC61BM (RMS of ~0.5 nm) blends. Stille cross coupling reaction for the synthesis of PTzBDT-1 and PTzBDT-2. Summary of the optical and electrochemical properties

One-pot synthesis of 4′-alkyl-4-cyanobiaryls on the basis of the terephthalonitrile dianion and neutral aromatic nitrile cross-coupling

• Roman Yu. Peshkov,
• Elena V. Panteleeva,
• Wang Chunyan,
• Evgeny V. Tretyakov and
• Vitalij D. Shteingarts

Beilstein J. Org. Chem. 2016, 12, 1577–1584, doi:10.3762/bjoc.12.153

• an alkyl halide. Earlier, we used butyl bromide for anion 3 trapping and obtained 4-butyl-4'-cyanobiphenyl (5aa) in 56% yield (Table 1, entry 1) [23]. In order to expand the scope of the synthetic utilization of the cross-coupling reaction under investigation, as well as to work out a short and

Star-shaped and linear π-conjugated oligomers consisting of a tetrathienoanthracene core and multiple diketopyrrolopyrrole arms for organic solar cells

• Hideaki Komiyama,
• Chihaya Adachi and
• Takuma Yasuda

Beilstein J. Org. Chem. 2016, 12, 1459–1466, doi:10.3762/bjoc.12.142

• cross-coupling reaction. Both TTA-DPP4 and TTA-DPP2 were soluble in common organic solvents, such as chloroform, toluene, and chlorobenzene. The thermal stability of these compounds was analyzed by thermogravimetric analysis (TGA). As shown in Figure 3, the 5% weight-loss temperature of TTA-DPP4 and TTA

Copper-catalyzed [3 + 2] cycloaddition of (phenylethynyl)di-p-tolylstibane with organic azides

• Mizuki Yamada,
• Mio Matsumura,
• Yuki Uchida,
• Masatoshi Kawahata,
• Yuki Murata,
• Naoki Kakusawa,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2016, 12, 1309–1313, doi:10.3762/bjoc.12.123

• electrophilic substitution and cross-coupling reaction are in progress. Experimental General procedure for the preparation of compounds 3: CuBr (3.6 mg, 0.025 mmol, 5 mol %), (phenylethynyl)di-p-tolylstibane (1, 203 mg, 0.5 mmol), and an organic azide (2, 0.5 mmol) were dissolved in THF (5 mL). The reaction

The role of alkyl substituents in deazaadenine-based diarylethene photoswitches

• Christopher Sarter,
• Michael Heimes and
• Andres Jäschke

Beilstein J. Org. Chem. 2016, 12, 1103–1110, doi:10.3762/bjoc.12.106

• position 8 of 7-deazaadenine. For the synthesis of these 8 compounds we used a convergent approach based on a central Suzuki cross-coupling reaction (Scheme 1). For the compounds with one methyl group (1a–d), 7-deaza-7-iodo-2’-deoxyadenosine was synthesized as described [48], while 7-deaza-7-iodo-8-methyl

A convenient route to symmetrically and unsymmetrically substituted 3,5-diaryl-2,4,6-trimethylpyridines via Suzuki–Miyaura cross-coupling reaction

• Dariusz Błachut,
• Joanna Szawkało and
• Zbigniew Czarnocki

Beilstein J. Org. Chem. 2016, 12, 835–845, doi:10.3762/bjoc.12.82

• unsymmetrically substituted diarylpyridines, difficult to access by other methods. Keywords: arylpyridines; cross coupling reaction; heteroaromatics; one-pot reaction; palladium catalyst; Introduction Nitrogen heterocycles are an important class of compounds widely present in agrochemical products [1][2] and

• less susceptible to the cross-coupling reaction. If the steric repulsion of the pyridine methyl group, at least in part, corresponds to its van der Waals radii, the degree of steric repulsion of the selected ortho-substituents in arylboronic acids can be listed in the following order: I > Br > Me > Cl

• toluene/H2O (6:1) was initially tested. Recently, several ligand-free catalytic systems have been applied successfully in Suzuki cross-coupling reaction between various aryl and heteroaryl halides and triflates with alkenyl and arylboronic acids [40][41][42][43]. The evaluation of such catalysts

Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

• Minh Anh Truong and
• Koji Nakano

Beilstein J. Org. Chem. 2016, 12, 805–812, doi:10.3762/bjoc.12.79

• are described in Scheme 1 and Scheme 2. 3-Decylanisole was first synthesized from commercially available 3-bromoanisole via iron-catalyzed cross-coupling reaction with decylmagnesium bromide in 71% yield [47]. Lithiation of the obtained 3-decylanisole with s-BuLi and the following treatment with 2

Studies on the synthesis of peptides containing dehydrovaline and dehydroisoleucine based on copper-mediated enamide formation

• Franziska Gille and
• Andreas Kirschning

Beilstein J. Org. Chem. 2016, 12, 564–570, doi:10.3762/bjoc.12.55

• protecting group and the reaction conditions. It was found that ornithine – a suitable precursor – is better suited than arginine for achieving good yields for the C–N cross-coupling reaction. The optimized conditions were utilized for the synthesis of peptides 32, 33, 39 and 40 containing a neighboring

• made responsible. Thus, this report covers our efforts to optimize the copper-mediated cross-coupling reaction in the preparation of dehydroamino acid containing peptide fragments present in myxovalargin (peptides containing amino acids 3-methylbutyric acid 1, 2, 7–9 and 11–13). Results and Discussion

• total synthesis when the guanidine group has either to be liberated by the removal of the protecting groups or used for the introduction to the corresponding ornithine residue. These results demonstrate that the copper-mediated cross-coupling reaction depends on the functional groups present in the

Copper-mediated arylation with arylboronic acids: Facile and modular synthesis of triarylmethanes

• H. Surya Prakash Rao and
• A. Veera Bhadra Rao

Beilstein J. Org. Chem. 2016, 12, 496–504, doi:10.3762/bjoc.12.49

• ligands as it is less expensive and more readily facilitates purification. Results and Discussion We selected the copper-mediated cross-coupling reaction of diphenylmethanol (9a) with phenylboronic acid (10a) for the synthesis of triphenylmethane (11a) to optimize the reaction conditions and catalyst

• stable C–C bond in 11, a Cu–O bond in 17, and boric acid at the cost of weak Ar–Cu and C–OH bonds in 16 and 9, respectively [52]. With the optimized reaction conditions in hand, we examined the scope of the cross-coupling reaction for the synthesis of a variety of triarylmethanes from diphenylmethanol

• towards electronic effects, the copper-mediated cross-coupling reaction is not very sensitive to steric crowding in the neighborhood of the reaction center. Next, we employed heteroaromatic boronic acids, such as furan-2-ylboronic acid (10i; Table 2, entry 8), thiophen-2-ylboronic acid (10j; Table 2

Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen

• Hans Sterckx,
• Johan De Houwer,
• Carl Mensch,
• Wouter Herrebout,
• Kourosch Abbaspour Tehrani and
• Bert U. W. Maes

Beilstein J. Org. Chem. 2016, 12, 144–153, doi:10.3762/bjoc.12.16

• . This compound is structurally interesting as it is activated by both a pyridin-2-yl and a quinolin-4-yl moiety (Scheme 2, bottom). The synthesis of substrate 12 was accomplished by a cross-coupling reaction of pyridine alcohol 11 with commercial 4-chloro-2,8-bis(trifluoromethyl)quinoline (7b) according

N-Methylphthalimide-substituted benzimidazolium salts and PEPPSI Pd–NHC complexes: synthesis, characterization and catalytic activity in carbon–carbon bond-forming reactions

• Senem Akkoç,
• Yetkin Gök,
• İlhan Özer İlhan and
• Veysel Kayser

Beilstein J. Org. Chem. 2016, 12, 81–88, doi:10.3762/bjoc.12.9

• with 4-chlorotoluene. Keywords: arylation; benzimidazolium salts; catalysis; N-heterocyclic carbene; PEPPSI complex; Suzuki–Miyaura cross-coupling reaction; Introduction The use of N-heterocyclic carbenes (NHCs) as ligands was started by Wanzlick [1] and Öfele [2] almost fifty years ago. There have

• –Miyaura cross-coupling reaction. The compounds were found to be very efficient in the symmetric and asymmetric C–C bond-forming reactions. Results and Discussion Synthesis of N-methylphthalimide substituted benzimidazolium salts New benzimidazolium salts 1–4, which are carbene precursors, were synthesized

• compounds in Suzuki–Miyaura cross-coupling reaction The Suzuki–Miyaura cross-coupling reaction, which has mostly been performed in organic solvents until recently, can now be performed using green solvents under mild conditions [29][30][31][32][33][34]. We used H2O with DMF as solvents in different

Synthesis and photophysical characteristics of polyfluorene polyrotaxanes

• Aurica Farcas,
• Giulia Tregnago,
• Ana-Maria Resmerita,
• Pierre-Henri Aubert and
• Franco Cacialli

Beilstein J. Org. Chem. 2015, 11, 2677–2688, doi:10.3762/bjoc.11.288

• [2,7-(9,9-dioctylfluorene)-alt-2,7-fluorene/TM-βCD)] (3·TM-βCD) and poly[2,7-(9,9-dioctylfluorene)-alt-2,7-fluorene/TM-γCD)] (3·TM-γCD) polyrotaxanes have been synthesized. Thus, 3·TM-βCD and 3·TM-γCD have been obtained through the Suzuki cross-coupling reaction of 2,7-dibromofluorene (1) encapsulated

Synthesis of Xenia diterpenoids and related metabolites isolated from marine organisms

• Tatjana Huber,
• Lara Weisheit and
• Thomas Magauer

Beilstein J. Org. Chem. 2015, 11, 2521–2539, doi:10.3762/bjoc.11.273

• -membered carbocycle was realized via a B-alkyl Suzuki–Miyaura cross-coupling reaction. Optimization studies of this key ring closure with different protecting groups on the lactol functionality revealed methyl acetal 135 as the most efficient substrate for this transformation. The challenging key step was

Recent advances in copper-catalyzed C–H bond amidation

• Jie-Ping Wan and
• Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

• chloride/anhydrides [6][7][8][9][10][11], nitrile hydrolysis [12][13][14][15][16], Goldberg C–N cross coupling reaction [17], aldehyde/ketone amidation [18][19][20][21][22][23], the transamidation [24][25][26][27][28][29], and oxime rearrangement [30][31][32][33], to name only a few. It is obvious that the

The simple production of nonsymmetric quaterpyridines through Kröhnke pyridine synthesis

• Isabelle Sasaki,
• Jean-Claude Daran and
• Gérard Commenges

Beilstein J. Org. Chem. 2015, 11, 1781–1785, doi:10.3762/bjoc.11.193

• pathway [17][20], or a Suzuki–Miyaura cross-coupling reaction [21]. The use of triazine derivatives (which under particular conditions undergo an inverse Diels–Alder reaction) can also produce oligopyridines [22]. On the other hand, there are a limited number of reports dealing with the preparation of

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

• Louis P. Sandjo,
• Victor Kuete and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2015, 11, 1667–1699, doi:10.3762/bjoc.11.183

• successfully performed in six steps with an overall yield of 6.5%. The steps included an organometallic intermediate and a Negishi cross-coupling reaction characterized by a transmetalation with zinc and palladium. The benzonaphthyridinone product was transformed into a bromobenzonaphthyridine intermediate by