The chemistry of bisallenes

• Henning Hopf and
• Georgios Markopoulos

Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225

• ), but the composition of the product mixture is anything but simple (Scheme 5) [32][33][34][35][36]. Not only are the three isomeric C3-coupling products 38 to 40 produced, but also those of 37 with the Grignard reagent, 41 and 42 (R = Et, n-Pr). All of these C–C-coupling reactions are thought to occur

Syntheses and applications of furanyl-functionalised 2,2’:6’,2’’-terpyridines

• Jérôme Husson and
• Michael Knorr

Beilstein J. Org. Chem. 2012, 8, 379–389, doi:10.3762/bjoc.8.41

• literature example for this purpose uses the Stille reaction [33]. This C–C coupling, which involves the reaction between a halogenated or equivalent starting material and an organotin compound, was used to prepare 12 from 4′-(trifluoromethanesulfonyl)-2,2′′:6′,2′′-terpyridine (34) [34] and 2

Efficient synthesis of 1,3-diaryl-4-halo-1H-pyrazoles from 3-arylsydnones and 2-aryl-1,1-dihalo-1-alkenes

• Yiwen Yang,
• Chunxiang Kuang,
• Hui Jin,
• Qing Yang and
• Zhongkui Zhang

Beilstein J. Org. Chem. 2011, 7, 1656–1662, doi:10.3762/bjoc.7.195

• cycloaddition between 3-arylsydnones 1 and 2-aryl-1,1-dihalo-1-alkenes 2 (Scheme 1). 1,3-Diaryl-4-halo-1H-pyrazoles were found to be important intermediates that could easily be converted into 1,2,4-triaryl- or 1,2,5-triaryl-substituted pyrazoles via a Pd-catalyzed C–C coupling reaction. To the best of our

Pseudo five-component synthesis of 2,5-di(hetero)arylthiophenes via a one-pot Sonogashira–Glaser cyclization sequence

• Dominik Urselmann,
• Dragutin Antovic and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2011, 7, 1499–1503, doi:10.3762/bjoc.7.174

• title compounds. This novel pseudo five-component synthesis starting from iodo(hetero)arenes is particularly suitable as a direct access to well-defined thiophene oligomers, which are of peculiar interest in materials science. Keywords: C–C coupling; copper; multicomponent reactions; palladium

Access to pyrrolo-pyridines by gold-catalyzed hydroarylation of pyrroles tethered to terminal alkynes

• Elena Borsini,
• Gianluigi Broggini,
• Andrea Fasana,
• Chiara Baldassarri,
• Angelo M. Manzo and
• Alcide D. Perboni

Beilstein J. Org. Chem. 2011, 7, 1468–1474, doi:10.3762/bjoc.7.170

• -azepines. Keywords: C–C coupling; gold catalysis; homogeneous catalysis; nitrogen heterocycles; rearrangement; Introduction Intramolecular transition-metal-catalyzed reactions represent one of the most challenging routes for the preparation of heterocyclic compounds [1][2][3][4][5]. Methodologies

Amines as key building blocks in Pd-assisted multicomponent processes

• Didier Bouyssi,
• Nuno Monteiro and
• Geneviève Balme

Beilstein J. Org. Chem. 2011, 7, 1387–1406, doi:10.3762/bjoc.7.163

• . Synthesis of indoles through a sequential C–C coupling/desilylation–coupling/cyclization reaction. Synthesis of indoles by a site selective Pd/C catalyzed cross-coupling approach. Synthesis of isoindolin-1-one derivatives through a sequential Sonogashira coupling/carbonylation/hydroamination reaction

C–C (alkynylation) vs C–O (ether) bond formation under Pd/C–Cu catalysis: synthesis and pharmacological evaluation of 4-alkynylthieno[2,3-d]pyrimidines

• Dhilli Rao Gorja,
• K. Shiva Kumar,
• K. Mukkanti and
• Manojit Pal

Beilstein J. Org. Chem. 2011, 7, 338–345, doi:10.3762/bjoc.7.44

• position of a thieno[2,3-d]pyrimidine ring via C–C coupling under Pd/C–Cu catalysis. To the best of our knowledge, only two examples of similar coupling have been reported using the system (PPh3)2PdCl2/CuI as catalyst in the presence of Et3N [10]. The alkynyl substituent of compound 3 could be utilized for

Polar tagging in the synthesis of monodisperse oligo(p-phenyleneethynylene)s and an update on the synthesis of oligoPPEs

• Dhananjaya Sahoo,
• Susanne Thiele,
• Miriam Schulte,
• Navid Ramezanian and
• Adelheid Godt

Beilstein J. Org. Chem. 2010, 6, No. 57, doi:10.3762/bjoc.6.57

• -diiodobenzene a better procedure is presented together with the finding that 1,4-dialkyl-2,3-diiodobenzene, a constitutional isomer of 1,4-dialkyl-2,5-diiodobenzene, is one of the byproducts. Keywords: alkyne protecting group; carbometalation; C–C coupling; phenyleneethynylene; polar tagging; Introduction

C-Arylation reactions catalyzed by CuO-nanoparticles under ligand free conditions

• Mazaahir Kidwai,
• Saurav Bhardwaj and
• Roona Poddar

Beilstein J. Org. Chem. 2010, 6, No. 35, doi:10.3762/bjoc.6.35

• one of the most important reactions in organic synthesis [1][2][3]. The resulting compounds formed from C–C coupling are valuable synthons in organic synthesis [4][5][6][7]. However, C-arylation reactions have not been investigated to the same extent as other C–C bond forming reactions. A great deal

• NMR). Powder X-ray diffraction pattern and TEM image of nano CuO (fresh). Proposed reaction pathway for the CuO-nanoparticles catalyzed C–C coupling reaction. Powder X-ray diffraction pattern and TEM image of recycled CuO-nanoparticles. Synthesis of 3-phenylpentane-2,4-dione using CuO-nanoparticles

Solvent-free and time-efficient Suzuki–Miyaura reaction in a ball mill: the solid reagent system KF–Al₂O₃ under inspection

• Franziska Bernhardt,
• Ronald Trotzki,
• Tony Szuppa,
• Achim Stolle and
• Bernd Ondruschka

Beilstein J. Org. Chem. 2010, 6, No. 7, doi:10.3762/bjoc.6.7

• milling; C–C coupling; KF–Al2O3; palladium; solid reagent system; Introduction Over the last two decades, a major trend in the field of organic chemistry has been evident: environmentally friendly processes using safer reagents, generating fewer side products and requiring less use of solvents are in

• results in Figure 1 are restricted to one aryl bromide (2a), experiments were expanded by taking into account the ability of the substituents to influence the experimental results. Figure 2 shows the results of blank tests regarding the base component, in which the C–C coupling was carried out in the

• yield of coupling products 3 was observed while using KF-loaded aluminas, clearly indicating that a base is necessary for a successful C–C coupling reaction [33][34][36][37][38][39][40][41][42][57][58]. The purchased KF–Al2O3 (SRS4a) system shows the worst results for all tested aryl bromides, except

Pd/C- Mediated synthesis of indoles in water

• Mohosin Layek,
• Udaya Lakshmi,
• Dipak Kalita,
• Deepak K. Barange,
• Aminul Islam,
• K. Mukkanti and
• Manojit Pal

Beilstein J. Org. Chem. 2009, 5, No. 46, doi:10.3762/bjoc.5.46

• -alkynyl substituted N-methylaniline as a sole product rather than expected indole indicated that the presence of an electron donating group on the nitrogen was unfavourable for the cyclization step though the C–C coupling reaction proceeded well under the conditions employed. Having prepared a variety of

Polyionic polymers – heterogeneous media for metal nanoparticles as catalyst in Suzuki–Miyaura and Heck–Mizoroki reactions under flow conditions

• Klaas Mennecke and
• Andreas Kirschning

Beilstein J. Org. Chem. 2009, 5, No. 21, doi:10.3762/bjoc.5.21

• palladium catalyzed reactions have emerged as industrially very desirable processes and miniflow fixed bed reactors loaded with Pd(0) nanoparticles should be well suited to perform these C-C coupling reactions [34]. A particular challenge for utilizing the Suzuki–Miyaura reaction in flow devices is the

• industrial relevance is the Heck–Mizoroki reaction. We were able to perform C-C coupling reaction under flow conditions with aryl iodides 23–28 using catalyst 3 (Table 2). Optimization of the conditions for our monolithic flow reactor was conducted with 4′-iodoacetophenone (23) and styrene (29) as coupling

• with 4′-bromoacetophenone coupling with styrene yielded Heck-product 30 in only 35%. In order to generalize the reaction protocol different aryl iodides were coupled with styrene. In all cases, the C-C coupling products were formed within 0.5 to 24 h in very good yield with excellent stereocontrol (see