Decarboxylative and dehydrative coupling of dienoic acids and pentadienyl alcohols to form 1,3,6,8-tetraenes

• Ghina’a I. Abu Deiab,
• Mohammed H. Al-Huniti,
• I. F. Dempsey Hyatt,
• Emma E. Nagy,
• Kristen E. Gettys,
• Sommayah S. Sayed,
• Christine M. Joliat,
• Paige E. Daniel,
• Rupa M. Vummalaneni,
• Andrew T. Morehead Jr,
• Andrew L. Sargent and
• Mitchell P. Croatt

Beilstein J. Org. Chem. 2017, 13, 384–392, doi:10.3762/bjoc.13.41

• important problem in organic synthesis. Cross-coupling reactions provide avenues to these otherwise difficult reactions, but often require prefunctionalization of the coupling partners [1][2][3][4][5][6][7][8][9]. However, recent C–H activation research has enabled the use of further simplified starting

(Z)-Selective Takai olefination of salicylaldehydes

• Stephen M. Geddis,
• Caroline E. Hagerman,
• Warren R. J. D. Galloway,
• Hannah F. Sore,
• Jonathan M. Goodman and
• David R. Spring

Beilstein J. Org. Chem. 2017, 13, 323–328, doi:10.3762/bjoc.13.35

• , particularly in the field of total synthesis where it is often used to install vinyl iodides with high levels of geometric purity which can then be utilised in metal-catalysed cross-coupling reactions [2][6]. Hodgson et al. [7] and later Takai et al. [5] have proposed very similar models to explain the (E

Synthesis and optical properties of new 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles

• Anastasia S. Kostyuchenko,
• Tatyana Yu. Zheleznova,
• Anton J. Stasyuk,
• Aleksandra Kurowska,
• Wojciech Domagala,
• Adam Pron and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2017, 13, 313–322, doi:10.3762/bjoc.13.34

• elaboration of a new synthetic procedure. In this communication we present a detailed study of cross-coupling reactions between еthyl 3-decyl-2,2'-bithiophene-5-carboxylate and different aryl halides. The resulting esters are subsequently used as substrates in the preparation of new D–A–D compounds with an

Highly bulky and stable geometry-constrained iminopyridines: Synthesis, structure and application in Pd-catalyzed Suzuki coupling of aryl chlorides

• Yi Lai,
• Zhijian Zong,
• Yujie Tang,
• Weimin Mo,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen,
• Liqun Jin,
• Wen-hua Sun and
• Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 213–221, doi:10.3762/bjoc.13.24

• showed a good catalytic efficiency for both Suzuki and Heck cross-coupling reactions. The favorable effect originated from the ring-fused framework being able to establish a strained environment for better stability. Efficient couplings were achieved with aryl bromides or iodides as substrates, however

• up to 325 °C. With these sterically hindered iminopyridine–palladium complexes Pd1 to Pd5 in hand, we firstly investigated their catalytic activity directly in Suzuki cross-coupling reactions with chlorobenzene as the electrophile. The reactions were performed under the previously reported conditions

• , 27.9, 27.7, 27.2, 23.6, 23.5, 21.0; HRMS (ESI+) m/z: [M – Cl + CH3CN]+ calcd for C22H28ClN2Pd·CH3CN, 504.1235; found, 504.1231. General procedure for Pd-catalyzed Suzuki cross-coupling reactions To a Young tube, aryl chlorides (5.0 mmol), K2CO3 (1.5 g, 11 mmol), arylboric acid (6 mmol), complex Pd2

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

• in the literature for other palladium-catalyzed cross-coupling reactions [34][35][36], namely in some reactions involving halogenated porphyrin derivatives [37]. Presumably in this particular case the lack of efficiency of the catalytic system is probably responsible for this secondary reaction

• -catalyzed cross-coupling reaction between aryl halides and N-tosylhydrazones. A retrosynthetic scheme for the synthesis of β-alkenyl-type porphyrin derivatives from the Zn(II) complex of β-bromo-meso-tetraphenylporphyrin and N-tosylhydrazones. Palladium catalysed cross-coupling reactions between β

• -brominated porphyrin 1 and N-tosylhydrazones 2a–c. Results obtained in the palladium-catalyzed cross-coupling reactions between β-brominated porphyrin 1 with N-tosylhydrazones 2a–c. Supporting Information Supporting Information File 46: Copies of NMR, HRMS(ESI) and UV–vis spectra of the new derivatives

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

• -forming reactions such as Sonogashira, Heck, or Suzuki coupling reactions as well as a cyanation reaction. These cross-coupling reactions led to a series of 5-alkynyl-, 5-alkenyl-, 5-aryl- and 5-cyano-substituted 1,2-oxazine derivatives being of considerable interest for further synthetic elaborations

• . This was exemplarily demonstrated by the hydrogenation of syn-21 and anti-24 and by a click reaction of a 5-alkynyl-substituted precursor. Keywords: amino alcohol; click reaction; cross-coupling reactions; hydrogenation; iodination; 1,2-oxazines; Introduction Over the last decade, we have intensively

• [21][22]. We previously reported the synthesis of enantiopure 1,2-oxazin-4-yl nonaflates and phosphates starting from precursors of type 3 and their conversion into differently C-4-substituted products employing palladium-catalyzed cross-coupling reactions [23]. In a related study, we have also

Benzothiadiazole oligoene fatty acids: fluorescent dyes with large Stokes shifts

• Lukas J. Patalag and
• Daniel B. Werz

Beilstein J. Org. Chem. 2016, 12, 2739–2747, doi:10.3762/bjoc.12.270

• membranes. Results and Discussion Synthesis The most prominent methods to access oligoene structures are either cross-coupling reactions [17][18][19] or Wittig-type reactions [20][21][22]. The advantage of the latter ones is that they are often conducted at low temperatures and therefore are employed for

A versatile route to polythiophenes with functional pendant groups using alkyne chemistry

• Xiao Huang,
• Li Yang,
• Rikard Emanuelsson,
• Jonas Bergquist,
• Maria Strømme,
• Martin Sjödin and
• Adolf Gogoll

Beilstein J. Org. Chem. 2016, 12, 2682–2688, doi:10.3762/bjoc.12.265

• cross-coupling reactions, cycloaddition reactions, radical reactions and reductive addition reactions. A terminal alkyne can also react as nucleophile or serve as synthon for pyrrole rings [24][25]. Thus we here fuse the rich alkyne chemistry to the EDOT backbone, resulting in a novel EDOT derivative

From betaines to anionic N-heterocyclic carbenes. Borane, gold, rhodium, and nickel complexes starting from an imidazoliumphenolate and its carbene tautomer

• Ming Liu,
• Jan C. Namyslo,
• Martin Nieger,
• Mika Polamo and
• Andreas Schmidt

Beilstein J. Org. Chem. 2016, 12, 2673–2681, doi:10.3762/bjoc.12.264

• tautomer; imidazol-2-ylidene; mesoionic compound; mesomeric betaine; Introduction Since the first isolation of a stable N-heterocyclic carbene (NHC) [1] in 1991 this compound class has provided numerous highly efficient ligands of NHC-metal catalysts for cross-coupling reactions [2][3][4][5][6][7

Facile synthesis of a 3-deazaadenosine phosphoramidite for RNA solid-phase synthesis

• Elisabeth Mairhofer,
• Elisabeth Fuchs and
• Ronald Micura

Beilstein J. Org. Chem. 2016, 12, 2556–2562, doi:10.3762/bjoc.12.250

• yield. Unfortunately, all attempts of the authors to displace the second chlorine atom of the imidazo[4,5-c]pyridine nucleoside using sodium methoxide or palladium-catalyzed cross-coupling reactions as described in [26] failed. We therefore decided not to put additional efforts into this route. Attempts

Sydnone C-4 heteroarylation with an indolizine ring via Chichibabin indolizine synthesis

• Florin Albota,
• Mino R. Caira,
• Constantin Draghici,
• Florea Dumitrascu and
• Denisa E. Dumitrescu

Beilstein J. Org. Chem. 2016, 12, 2503–2510, doi:10.3762/bjoc.12.245

• ; Chichibabin synthesis; indolizine; pyridinium N-ylide; sydnone; Introduction In recent decades, interest in the syntheses of biheteroaryls has been focused on the creation of new hetaryl–hetaryl C(sp2)–C(sp2) bonds, in particular through cross-coupling reactions. These reactions are catalyzed by palladium or

• formation of single bonds between two aromatic or heteroaromatic rings involves palladium-catalyzed cross-coupling reactions and cyclization of functional groups attached to an aromatic and heteroaromatic ring. Thus, arylation and heteroarylation at the C-4 position of sydnones has been performed by

• palladium-catalyzed cross-coupling reactions [32][33][34][35][36] starting from 4-unsubstituted sydnones, 4-halosydnones or by chemical transformation of the substituents attached to C-4 [32][33][34][35][36]. Herein, using the Chichibabin indolizine reaction one of the simplest and most efficient methods

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• π-bridges by simple Suzuki–Miyaura cross-coupling reactions could be completed. Starting with commercially available 5-bromothiophene-2-carboxaldehyde and then reaction with 3a–c to generate the required bithiophenes, then terthiophenes, while further catenation with 3b resulted in synthesis of the

Rapid regio- and multi-coupling reactivity of 2,3-dibromobenzofurans with atom-economic triarylbismuths under palladium catalysis

• Maddali L. N. Rao,
• Jalindar B. Talode and
• Venneti N. Murty

Beilstein J. Org. Chem. 2016, 12, 2065–2076, doi:10.3762/bjoc.12.195

• bromobenzofurans were not reported so far (Scheme 1) [35]. Given the importance of threefold couplings’ reactivity realized with the sub-stoichiometric loading of triarylbismuths in the cross-coupling reactions [35][36][37][38][39][40][41][42], we report herein, a novel regio- and multi-coupling of

Synthesis and characterization of fluorinated azadipyrromethene complexes as acceptors for organic photovoltaics

• Forrest S. Etheridge,
• Roshan J. Fernando,
• Sandra Pejić,
• Matthias Zeller and
• Geneviève Sauvé

Beilstein J. Org. Chem. 2016, 12, 1925–1938, doi:10.3762/bjoc.12.182

• analogs for the synthesis of L3 and L4 were synthesized according to literature procedures and used without purification [35][36]. The Stille cross coupling reactions for the synthesis of L3 and L4 were monitored by MALDI–TOF–MS and were found to not be complete after increasing the reaction time to 48 h

Practical synthetic strategies towards lipophilic 6-iodotetrahydroquinolines and -dihydroquinolines

• David R. Chisholm,
• Garr-Layy Zhou,
• Ehmke Pohl,
• Roy Valentine and
• Andrew Whiting

Beilstein J. Org. Chem. 2016, 12, 1851–1862, doi:10.3762/bjoc.12.174

• para-position relative to nitrogen (the 6-position) was required for further functionalisation by typical cross-coupling reactions. THQ scaffolds similar to 1 are known in the literature, and have been typically prepared by two approaches. The first involves the alkylation of the starting aniline with

• was to synthesise THQs and DHQs of the general scaffold 1 for the use in a variety of cross-coupling reactions, thus necessitating the presence of a halogen or pseudohalogen in the para-position relative to nitrogen. Most of the relevant literature focuses on the synthesis of the corresponding aryl

• bromides or aryl chlorides, but initial investigation with 6-bromo-THQs indicated that these were remarkably unreactive in cross-coupling reactions [14], and a reliable and scalable synthesis of the likely more reactive iodides was, therefore, sought. We first considered the retrosynthetic analysis shown

Methylpalladium complexes with pyrimidine-functionalized N-heterocyclic carbene ligands

• Dirk Meyer and
• Thomas Strassner

Beilstein J. Org. Chem. 2016, 12, 1557–1565, doi:10.3762/bjoc.12.150

• ]. One of the most prominent examples are the palladium catalyzed cross-coupling reactions [2], but in addition palladium complexes recently received much attention also in the field of selective CH oxidations [3][4][5][6]. The catalytic conversion of alkanes and especially of methane into a value-added

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

• organoantimony compounds in organic synthesis has attracted much interest during the last two decades [25][26]. Trivalent organoantimony compounds (stibanes) such as aryl- and ethynylstibanes are useful transmetalation agents in Pd-catalyzed cross-coupling reactions with aryl halides and acyl chlorides [27][28

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• arylureas at room temperature. A commercially available catalyst [Pd(MeCN)4](BF4)2 or a nitrile-free cationic palladium(II) complex generated in situ from the reaction of Pd(OAc)2 and HBF4, effectively catalyzes C–H activation/cross-coupling reactions between aryl iodides, arylboronic acids and acrylates

• ), while acrylamides having simple amine or amino acid moieties also participated in cross-coupling reactions with the arylurea to produce the corresponding amide derivatives in moderate to good yields (5s, 5t). Total synthesis of boscalid® via C–H activation The rationale behind the attention recently

• , affording the coupling product and Pd(0). The resulting Pd(0) is then oxidized with BQ to regenerate the dicationic palladium species, which can re-enter the catalytic cycle. Arylation with an aryl iodide. Coupling reactions of aryl iodides have fewer similarities in terms of traditional cross-coupling

Enantioselective carbenoid insertion into C(sp³)–H bonds

• J. V. Santiago and
• A. H. L. Machado

Beilstein J. Org. Chem. 2016, 12, 882–902, doi:10.3762/bjoc.12.87

• activation; chiral catalysis; diazo compounds; total synthesis; Introduction One of the major challenges met in organic synthesis is the formation of carbon–carbon bonds, in particular in a stereoselective way. Nucleophilic substitution reactions, radical reactions, cross-coupling reactions and the Heck

Bi- and trinuclear copper(I) complexes of 1,2,3-triazole-tethered NHC ligands: synthesis, structure, and catalytic properties

• Shaojin Gu,
• Jiehao Du,
• Jingjing Huang,
• Huan Xia,
• Ling Yang,
• Weilin Xu and
• Chunxin Lu

Beilstein J. Org. Chem. 2016, 12, 863–873, doi:10.3762/bjoc.12.85

• and platinum complexes containing 1,2,3-triazole-tethered NHC ligands. The obtained palladium complexes displayed high activity in aqueous Suzuki–Miyaura cross-coupling reactions. We are interested in the synthesis and use of functionalized NHC ligands [20][28][29][30][31]. Herein, the synthesis

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

• leading to a number of different 2,4- and 2,5-diaryldimethylpyridines P3, P4 [25], 4-benzylpyrimidines P2 [26], and 4-methyl-5-arylpyrimidines P1 [26] was needed. For this purpose, we successfully used Suzuki and Negishi cross-coupling reactions between arylboronic acids/benzylzinc reagents and

• /arylboronic acid ratio was gradually increased, also the increased presence of the dicoupled product was observed. However, the final separated yield decreased and most of the starting material could be recovered. Another important problem in sequential cross-coupling reactions is the proper choice of

Iridium/N-heterocyclic carbene-catalyzed C–H borylation of arenes by diisopropylaminoborane

• Mamoru Tobisu,
• Takuya Igarashi and
• Naoto Chatani

Beilstein J. Org. Chem. 2016, 12, 654–661, doi:10.3762/bjoc.12.65

• to introduce Suginome’s dan group, which allows us to use the borylated products in more elaborate manner, such as iterative cross-coupling reactions [20]. Conclusion We have developed a C–H borylation of arenes and heteroarenes using diisopropylaminoborane as a borylating reagent. An iridium(I

Synthesis and nucleophilic aromatic substitution of 3-fluoro-5-nitro-1-(pentafluorosulfanyl)benzene

• Javier Ajenjo,
• Martin Greenhall,
• Camillo Zarantonello and
• Petr Beier

Beilstein J. Org. Chem. 2016, 12, 192–197, doi:10.3762/bjoc.12.21

• -coupling reactions [25][26][27]. Synthetic methods to novel SF5-containing building blocks are sought after and drive the development of applications of these compounds. In this work, we explore SNAr chemistry of 3-fluoro-5-nitro-1-(pentafluorosulfanyl)benzene which was initially obtained as a minor

• , nitro(pentafluorosulfanyl)benzenes are widely-available primary industrial products and starting materials to other SF5-benzenes which were prepared by reduction followed by condensation or diazotization chemistry [8][14][15][16], SEAr [17], SNAr [18][19][20][21][22][23][24], or metal-catalyzed cross

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

• spectroscopic methods (1H and 13C{1H} NMR, UV–vis, ESI-FTICR-MS, FTIR) and elemental analysis. The PEPPSI Pd–NHC complexes were tested for catalytic activities both in direct arylation and Suzuki–Miyaura cross-coupling reactions. The catalytic activities of benzimidazolium salts were only tested in a Suzuki

• –NHC complexes as catalysts were studied in Suzuki–Miyaura cross-coupling reactions without an inert atmosphere. Both complex types were quite effective in the coupling of 4-chlorotoluene with 4-tert-butylphenylboronic acid. (A) UV–vis absorbance spectra were taken in DMSO. (B) The second derivative of

Carbon–carbon bond cleavage for Cu-mediated aromatic trifluoromethylations and pentafluoroethylations

• Tsuyuka Sugiishi,
• Hideki Amii,
• Kohsuke Aikawa and
• Koichi Mikami

Beilstein J. Org. Chem. 2015, 11, 2661–2670, doi:10.3762/bjoc.11.286

• of CF3Cu, which participated in cross-coupling reactions with ArB(OH)2 in air [49]. Starting from CF3CO2Et or C2F5CO2Et, Mikami et al. obtained CF3Cu [44] or C2F5Cu [45]. The substrate scope of trifluoromethylation and pentafluoroethylation suggests that CF3Cu and C2F5Cu reagents are useful CnF2n+1