C-5’-Triazolyl-2’-oxa-3’-aza-4’a-carbanucleosides: Synthesis and biological evaluation

• Roberto Romeo,
• Caterina Carnovale,
• Salvatore V. Giofrè,
• Maria A. Chiacchio,
• Adriana Garozzo,
• Emanuele Amata,
• Giovanni Romeo and
• Ugo Chiacchio

Beilstein J. Org. Chem. 2015, 11, 328–334, doi:10.3762/bjoc.11.38

• natural nucleobases with unnaturally-substituted heteroaromatics or homoaromatic systems, or the modification of the phosphate P(O)–O–C bond with the non–hydrolyzable phosphonate P(O)–C linkage [17][18]. In this context, nucleoside analogues, where different carbon or heterocyclic systems replace the

Palladium-catalyzed 2,5-diheteroarylation of 2,5-dibromothiophene derivatives

• Fatma Belkessam,
• Aidene Mohand,
• Jean-François Soulé,
• Abdelhamid Elias and
• Henri Doucet

Beilstein J. Org. Chem. 2014, 10, 2912–2919, doi:10.3762/bjoc.10.309

• ][9][10][11][12][13][14][15][16]. However, an organometallic derivative must be prepared to perform such reactions. In 1990, Ohta and co-workers reported the Pd-catalyzed direct arylation of heteroaromatics using aryl halides as coupling partners via a C–H bond activation [17][18]. Since then Pd

Hindered aryl bromides for regioselective palladium-catalysed direct arylation at less favourable C5-carbon of 3-substituted thiophenes

• Rongwei Jin,
• Charles Beromeo Bheeter and
• Henri Doucet

Beilstein J. Org. Chem. 2014, 10, 1239–1245, doi:10.3762/bjoc.10.123

• -substituted heteroaromatics. Experimental General All reactions were perfomed in Schlenk tubes under argon. DMA analytical grade was not distilled before use. Commercial aryl bromide derivatives were used without purification. 1H NMR (400 MHz), 13C NMR (100 MHz) spectra were recorded in CDCl3 solutions on

The Flögel-three-component reaction with dicarboxylic acids – an approach to bis(β-alkoxy-β-ketoenamides) for the synthesis of complex pyridine and pyrimidine derivatives

• Mrinal K. Bera,
• Moisés Domínguez,
• Paul Hommes and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2014, 10, 394–404, doi:10.3762/bjoc.10.37

• aromatic rings. Flögel-three-component reaction of lithiated alkoxyallenes, nitriles and carboxylic acids providing β-alkoxy-β-ketoenamides 1 – versatile precursors for the synthesis of functionalized N-heteroaromatics 2–6. Synthesis of bis(β-ketoenamides) 13–15 by three-component reactions of lithiated

Copper-catalyzed trifluoromethylation of alkenes with an electrophilic trifluoromethylating reagent

• Xiao-Ping Wang,
• Jin-Hong Lin,
• Cheng-Pan Zhang,
• Ji-Chang Xiao and
• Xing Zheng

Beilstein J. Org. Chem. 2013, 9, 2635–2640, doi:10.3762/bjoc.9.299

• aromatic alkenes with electrophilic trifluoromethylation reagents in the presence of copper and base. Results and Discussion Previously, we reported that copper powder or cuprous iodide could promote trifluoromethylation of heteroaromatics, arylboronic acids or terminal alkynes with trifluoromethyl

New developments in gold-catalyzed manipulation of inactivated alkenes

• Michel Chiarucci and
• Marco Bandini

Beilstein J. Org. Chem. 2013, 9, 2586–2614, doi:10.3762/bjoc.9.294

• , affording 5-, 6-membered lactams and spiro-lactams 61 in excellent yields and high trans diastereoselectivity (Scheme 16). 4.2 The hydroarylation reaction In addition to methylene active compounds, electron-rich benzenes and heteroaromatics can be added to gold activated alkenes under suitable conditions

Recent advances in transition metal-catalyzed Csp²-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

• Grégory Landelle,
• Armen Panossian,
• Sergiy Pazenok,
• Jean-Pierre Vors and
• Frédéric R. Leroux

Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287

• investigations on the perfluoroalkylation of alkenes, aromatics and heteroaromatics catalyzed by Ru(II)Cl2(PPh3)3 [98][99][100][101][102][103][104]. In the course of their initial studies [98][100] aimed at the perfluoroalkylchlorination of terminal alkenes, they noticed that the corresponding 1-perfluoroalkyl

The chemistry of amine radical cations produced by visible light photoredox catalysis

• Jie Hu,
• Jiang Wang,
• Theresa H. Nguyen and
• Nan Zheng

Beilstein J. Org. Chem. 2013, 9, 1977–2001, doi:10.3762/bjoc.9.234

• sizes and acyclic amines underwent the α-arylation reaction to provide benzylic amines. The arylating reagents were benzonitriles substituted with an electron-withdrawing group. The nitrile group functioned as the leaving group. In some classes of five-membered heteroaromatics, a chloride was capable of

Inter- and intramolecular enantioselective carbolithiation reactions

• Asier Gómez-SanJuan,
• Nuria Sotomayor and
• Esther Lete

Beilstein J. Org. Chem. 2013, 9, 313–322, doi:10.3762/bjoc.9.36

• synthesis of chiral aromatics and heteroaromatics, such as isoquinolines or benzofurans, though lower yields and ee were obtained [15]. On the other hand, α-aryl O-(α-arylalkenyl) carbamates (α-carbamoyloxy-substituted styrenes) such as 14 undergo facile intermolecular carbolithiation reactions, via

N-Heterocyclic carbene–palladium catalysts for the direct arylation of pyrrole derivatives with aryl chlorides

• Ismail Özdemir,
• Nevin Gürbüz,
• Nazan Kaloğlu,
• Öznur Doğan,
• Murat Kaloğlu,
• Christian Bruneau and
• Henri Doucet

Beilstein J. Org. Chem. 2013, 9, 303–312, doi:10.3762/bjoc.9.35

• palladium-catalyzed direct arylation of various heteroaromatics including pyrroles by a C–H bond activation using aryl halides has met great success in recent years, allowing the synthesis of a wide variety of arylated heteroaromatics in only one step [20][21][22][23][24][25]. However, there are still

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

• very interesting, since combining the intrinsic properties of the two heteroaromatics should allow both the preparation of original molecular compounds and the conception of advanced (polymeric) materials featuring novel properties. We have recently reviewed this concept for thienyl-functionalised

Recent advances in direct C–H arylation: Methodology, selectivity and mechanism in oxazole series

• Cécile Verrier,
• Pierrik Lassalas,
• Laure Théveau,
• Guy Quéguiner,
• François Trécourt,
• Francis Marsais and
• Christophe Hoarau

Beilstein J. Org. Chem. 2011, 7, 1584–1601, doi:10.3762/bjoc.7.187

• –deprotonation (CMD) mechanism [19][69], which has now proved to be effective for a broad range of aromatics and heteroaromatics, including electron-rich as well as electron-deficient heterocycles [20][21][70]. Although Fagnou demonstrated the good reactivity of several azoles under CMD conditions [70], Strotman

Directed aromatic functionalization

• Victor Snieckus

Beilstein J. Org. Chem. 2011, 7, 1215–1218, doi:10.3762/bjoc.7.141

• heteroaromatics [15][16][17]. While comparison with SEAr and SNAr should never be denied, the DoM approach offers incontestable ortho regioselectivity, mild conditions, and perhaps most significantly, broad post-DoM synthetic potential. As a result, it has been called upon, with increasing favor and frequency, by

• sp, sp2, and sp3, and –O, –N, and –S bonds are made to the aromatic ring carbon [25]. These strategies rapidly furnish biaryls/heterobiaryls, and condensed complex aromatics/heteroaromatics whose construction by previous generation methods (e.g., diazonium and radical coupling) has been clearly

Palladium- and copper-mediated N-aryl bond formation reactions for the synthesis of biological active compounds

• Carolin Fischer and
• Burkhard Koenig

Beilstein J. Org. Chem. 2011, 7, 59–74, doi:10.3762/bjoc.7.10

• synthesis of complex molecules such as natural products or drugs is, in comparison to standard small-molecule N-arylation, not always straightforward and requires specially optimized conditions. Since amine- and amide-substituted aromatics and heteroaromatics are typical structures in medicinal chemistry

Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation

• Vladimir N. Boiko

Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88

• in Scheme 35 [118]. It should be noted that the tellurium reagent, Me3SnTeCF3, is capable of introducing the TeCF3 group into activated heteroaromatics [119]. In the reaction shown (Scheme 36) the use of three equivalents resulted in the introduction of only two TeCF3 groups. The Sandmeyer reaction

Shelf-stable electrophilic trifluoromethylating reagents: A brief historical perspective

• Norio Shibata,
• Andrej Matsnev and
• Dominique Cahard

Beilstein J. Org. Chem. 2010, 6, No. 65, doi:10.3762/bjoc.6.65

• , trifluoromethylacetyl and trifluoromethylsulfonyl derivatives, S-trifluoromethyl xanthates and others [6]. These reagents are well-suited for trifluoromethylation of aromatics, heteroaromatics and unsaturated double bonds [7]. Nucleophilic trifluoromethylation probably represents the most versatile and actively studied

Fused bicyclic piperidines and dihydropyridines by dearomatising cyclisation of the enolates of nicotinyl-substituted esters and ketones

• Heloise Brice,
• Jonathan Clayden and
• Stuart D. Hamilton

Beilstein J. Org. Chem. 2010, 6, No. 22, doi:10.3762/bjoc.6.22

• %, MNH4+); (Found: MH+, 258.1340. C12H19NO5 requires MH+, 258.1336). Coupling constants (Hz) in the major diastereoisomer of 15. Determination of the stereochemistry of 20b. Arrows indicate nuclear Overhauser enhancements. Dearomatising cyclisations (a) of enolates; (b) of electron-rich heteroaromatics