Olefin metathesis in air

• Lorenzo Piola,
• Fady Nahra and
• Steven P. Nolan

Beilstein J. Org. Chem. 2015, 11, 2038–2056, doi:10.3762/bjoc.11.221

• metal-catalyzed alkene metathesis [1][2][3][4][5][6][7][8][9][10], which involves a fragment exchange between alkenes, is nowadays one of the most used strategies for the formation of carbon–carbon bonds. This area of study began with a “black box” approach for catalysts formation in polymerization of

• been made to render catalysts more stable and yet more functional group tolerant. This review summarizes the major developments concerning catalytic systems directed towards water and air tolerance. Keywords: air stability; catalysis; olefin metathesis; RCM; ROMP; ruthenium; Introduction Transition

Efficient synthesis of π-conjugated molecules incorporating fluorinated phenylene units through palladium-catalyzed iterative C(sp²)–H bond arylations

• Fatiha Abdelmalek,
• Fazia Derridj,
• Safia Djebbar,
• Jean-François Soulé and
• Henri Doucet

Beilstein J. Org. Chem. 2015, 11, 2012–2020, doi:10.3762/bjoc.11.218

• in high yields in only a few steps with the respect of the environment [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Since the reports on transition metal-catalyzed direct arylation of polyfluorobenzenes by Fagnou (Figure 1b) [26], and others [27][28][29][30][31][32][33

Synthesis of quinoline-3-carboxylates by a Rh(II)-catalyzed cyclopropanation-ring expansion reaction of indoles with halodiazoacetates

• Magnus Mortén,
• Martin Hennum and
• Tore Bonge-Hansen

Beilstein J. Org. Chem. 2015, 11, 1944–1949, doi:10.3762/bjoc.11.210

• transition metal-catalyzed C–H functionalization by diazo compounds [5][6][7][8]. The reactions of indoles with electrophilic metal-bound carbenes, or carbenoids, generated from diazo compounds, takes place under mild reaction conditions. The reaction has been studied for the three principle classes of

Pyridine-promoted dediazoniation of aryldiazonium tetrafluoroborates: Application to the synthesis of SF₅-substituted phenylboronic esters and iodobenzenes

• George Iakobson,
• Junyi Du,
• Alexandra M. Z. Slawin and
• Petr Beier

Beilstein J. Org. Chem. 2015, 11, 1494–1502, doi:10.3762/bjoc.11.162

• -science [6][18][33][34][35][36][37][38], and material sciences [5][19][38][39] are emerging. Arylboronic acids and arylboronates represent versatile building blocks in organic synthesis [40]. They have found wide applications in transition metal-catalyzed cross-coupling reactions [41][42]. These boron

Deproto-metallation of N-arylated pyrroles and indoles using a mixed lithium–zinc base and regioselectivity-computed CH acidity relationship

• Mohamed Yacine Ameur Messaoud,
• Ghenia Bentabed-Ababsa,
• Madani Hedidi,
• Aïcha Derdour,
• Floris Chevallier,
• Yury S. Halauko,
• Oleg A. Ivashkevich,
• Vadim E. Matulis,
• Laurent Picot,
• Valérie Thiéry,
• Thierry Roisnel,
• Vincent Dorcet and
• Florence Mongin

Beilstein J. Org. Chem. 2015, 11, 1475–1485, doi:10.3762/bjoc.11.160

• the formed aryl iodides by recourse to transition metal-catalyzed coupling reactions [37]. When bis-heterocyclic compound 1a was reacted in THF for 2 h at room temperature with the lithium–zinc base, in situ prepared from ZnCl2·TMEDA (0.5 equiv) and LiTMP (1.5 equiv), a selective deprotonation at the

• obtained together with recovered starting material. In order to test the functionalization of the above synthesized aryl iodides through a subsequent transition-metal-catalyzed coupling reaction we subjected three of them to a copper-catalyzed N-arylation reaction. Thus, the iodides 3b, 3d and 4d were

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• -unsaturated amides and lactams, which remains an area that is underdeveloped. 2.3 Other transition-metal-catalyzed ECA reactions Though the majority of the reports on ECA of α,β-unsaturated amides and lactams utilize copper and rhodium as catalysts, other transition metals have also been used in these

Direct access to pyrido/pyrrolo[2,1-b]quinazolin-9(1H)-ones through silver-mediated intramolecular alkyne hydroamination reactions

• Hengshuai Wang,
• Shengchao Jiao,
• Kerong Chen,
• Xu Zhang,
• Linxiang Zhao,
• Dan Liu,
• Yu Zhou and
• Hong Liu

Beilstein J. Org. Chem. 2015, 11, 416–424, doi:10.3762/bjoc.11.47

• dangerous substrates bearing an azide group, and require a high reaction temperature and a long reaction time [2][10]. Recently, transition metal catalyzed hydroamination of alkynes [14][15][16][17][18][19][20][21][22][23][24][25][26], alkenes [15][27][28][29][30][31] and dienes [32][33] has been widely

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• compounds [15], the Pd(II)-catalyzed oxidative C–C, C–O, and C–N bond formation [3], the transition metal-catalyzed etherification of unactivated C–H bonds [19], the Pd(II)-catalyzed oxidative functionalization at the allylic position of alkenes [20][21], the oxidative functionalization catalyzed by copper

• compounds to form C–C, C–N, C–O, C–Hal, C–P, and N–N bonds [10], the Bu4NI/t-BuOOH oxidative system [22], selective functionalization of molecules [23], the oxidative esterification and oxidative amidation of aldehydes [24], and the transition metal-catalyzed radical oxidative cross-couplings [13]. The

An improved procedure for the preparation of Ru(bpz)₃(PF₆)₂ via a high-yielding synthesis of 2,2’-bipyrazine

• Danielle M. Schultz,
• James W. Sawicki and
• Tehshik P. Yoon

Beilstein J. Org. Chem. 2015, 11, 61–65, doi:10.3762/bjoc.11.9

• bpz have been reported [26][27][28], the most common of which involve transition metal-catalyzed reductive homocouplings of halopyrazine electrophiles [29][30]. However, we found these procedures to be capricious in our hands, and after a survey of known reductive dimerization protocols, the highest

Sequential decarboxylative azide–alkyne cycloaddition and dehydrogenative coupling reactions: one-pot synthesis of polycyclic fused triazoles

• Kuppusamy Bharathimohan,
• Thanasekaran Ponpandian,
• A. Jafar Ahamed and
• Nattamai Bhuvanesh

Beilstein J. Org. Chem. 2014, 10, 3031–3037, doi:10.3762/bjoc.10.321

• describe a one-pot protocol for the synthesis of a novel series of polycyclic triazole derivatives. Transition metal-catalyzed decarboxylative CuAAC and dehydrogenative cross coupling reactions are combined in a single flask and achieved good yields of the respective triazoles (up to 97% yield). This

• (90–105 kcal/mol) to form a new, weaker C–M bond (50–80 kcal/mol), followed by generation of a new C–C bond. Generally, transition metal-catalyzed sp2 C–H activation is facilitated by directing groups [10][11][12][13] or heteroatoms in the heterocyclic compounds [14][15][16][17][18]. This methodology

Exploration of C–H and N–H-bond functionalization towards 1-(1,2-diarylindol-3-yl)tetrahydroisoquinolines

• Michael Ghobrial,
• Marko D. Mihovilovic and
• Michael Schnürch

Beilstein J. Org. Chem. 2014, 10, 2186–2199, doi:10.3762/bjoc.10.226

• towards 1-(1,2-diarylindol-3-yl)-N-PG-THIQs (PG = protecting group, THIQ = tetrahydroisoquinoline) employing transition metal-catalyzed C–H and N–H-bond functionalization were explored. It was found that the synthesis of the target compounds is strongly dependent on the order of events. Hence, depending

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

• . China 10.3762/bjoc.10.215 Abstract Chiral phosphorus ligands have been widely used in transition metal-catalyzed asymmetric reactions. Herein, we report a new synthesis approach of chiral biaryls containing a phosphorus moiety using P(O)R2-directed Pd-catalyzed C–H activation; the functionalized

A new charge-tagged proline-based organocatalyst for mechanistic studies using electrospray mass spectrometry

• J. Alexander Willms,
• Rita Beel,
• Martin L. Schmidt,
• Christian Mundt and
• Marianne Engeser

Beilstein J. Org. Chem. 2014, 10, 2027–2037, doi:10.3762/bjoc.10.211

• as a function of time [8] and beyond that a characterization of transient intermediates by tandem mass spectrometry. ESI mass-spectrometric mechanistic studies have been reported for a broad range of reaction types ranging from transition metal-catalyzed polymerization [6][9] and coupling reactions

A tandem Mannich addition–palladium catalyzed ring-closing route toward 4-substituted-3(2H)-furanones

• Jubi John,
• Eliza Târcoveanu,
• Peter G. Jones and
• Henning Hopf

Beilstein J. Org. Chem. 2014, 10, 1462–1470, doi:10.3762/bjoc.10.150

• [19][20][21][22][23][24][25][26]. Synthetic routes for the preparation of these compounds involve transformations of substituted α-hydroxy-1,3-diketones [15][17], substituted furans [27][28][29], cyclization of allenic hydroxyketones [30], transition metal-catalyzed strategies (Au [31][32][33], Pt [34

Design and synthesis of multivalent neoglycoconjugates by click conjugations

• Feiqing Ding,
• Li Ji,
• Ronny William,
• Hua Chai and
• Xue-Wei Liu

Beilstein J. Org. Chem. 2014, 10, 1325–1332, doi:10.3762/bjoc.10.134

• irradiation, which is best known to accelerate transition metal-catalyzed homogeneous reactions [54]. Microwave-assisted organic reactions are rapidly becoming recognized as a valuable tool for facilitating a wide variety of organic transformations [55][56]. Finally, we found that the rate of conversion

Synthesis of chiral N-phosphoryl aziridines through enantioselective aziridination of alkenes with phosphoryl azide via Co(II)-based metalloradical catalysis

• Jingran Tao,
• Li-Mei Jin and
• X. Peter Zhang

Beilstein J. Org. Chem. 2014, 10, 1282–1289, doi:10.3762/bjoc.10.129

• commercially available phosphoryl chlorides, have been recently explored as nitrene sources for transition metal-catalyzed nitrene transfer reactions [20][21][22][23]. Their use in a catalytic asymmetric aziridination would provide an attractive approach for the synthesis of valuable chiral phosphorous

Synthesis of 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene ligands and their application in regio- and enantioselective Pd-catalyzed allylic alkylation of monosubstituted allyl substrates

• Zeng-Wei Lai,
• Rong-Fei Yang,
• Ke-Yin Ye,
• Hongbin Sun and
• Shu-Li You

Beilstein J. Org. Chem. 2014, 10, 1261–1266, doi:10.3762/bjoc.10.126

• alkylation reactions of monosubstituted allylic substrates. Inspired by these pioneering studies above and as our continuing interests in the transition metal-catalyzed asymmetric allylic alkylation reaction [35][36][37][38], we envisaged that the 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene

• . Preliminary explanation of the regioselectivity. Transition metal-catalyzed allylic substitution reactions with monosubstituted allyl substrates. Preparation of 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene ligands. Reagents and conditions: (a) (i) n-BuLi, TMEDA, Et2O, rt; (ii) (BrCF2)2, −78 °C. (b

Synthesis of ethoxy dibenzooxaphosphorin oxides through palladium-catalyzed C(sp²)–H activation/C–O formation

• Seohyun Shin,
• Dongjin Kang,
• Woo Hyung Jeon and
• Phil Ho Lee

Beilstein J. Org. Chem. 2014, 10, 1220–1227, doi:10.3762/bjoc.10.120

• ; Introduction Unreactive C(sp2)–H and C(sp3)–H bonds are ubiquitous in organic compounds [1][2][3][4][5][6][7], so that the development of methods for the transition metal-catalyzed C–H activation is one of the challenging goals in organic synthesis. Especially, the development of synthetic methods of C

One-pot three-component synthesis and photophysical characteristics of novel triene merocyanines

• Christian Muschelknautz,
• Robin Visse,
• Jan Nordmann and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2014, 10, 599–612, doi:10.3762/bjoc.10.51

• , and photophysics. Inspired by the concept of a diversity-oriented synthetic approach to chromophores [19][20][21][22][23][24][25][26] we have launched a program to apply transition metal-catalyzed processes as an entry to consecutive multicomponent [27][28] and domino reactions [29]. These highly

Preparation of new alkyne-modified ansamitocins by mutasynthesis

• Kirsten Harmrolfs,
• Lena Mancuso,
• Binia Drung,
• Florenz Sasse and
• Andreas Kirschning

Beilstein J. Org. Chem. 2014, 10, 535–543, doi:10.3762/bjoc.10.49

• compound 9 (see Supporting Information File 1 for further details). In addition to the formation of the bromo-ansamitocin derivatives, also the detoxification products 22g and 22h were isolated in 0.1% yield. The bromo-ansamitocins can be regarded to be an ideal starting material for transition metal

• -catalyzed coupling reactions. Due to the low product yield obtained with mutasynthon 9, for which the steric demand of the bromo substituent can likely be made responsible, we switched the strategy towards the direct introduction of an alkyne moiety by a mutasynthetic approach. Feeding of alkynyl(amino

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

• the range of 60–72%. Pyrid-4-yl nonaflates are excellent precursors for transition metal-catalyzed cross-coupling reactions [42][54][55][56][57][58], which was demonstrated here by the successful Suzuki coupling of bisnonaflate 19 with (E)-styrylboronic acid and the Stille coupling of 19 with 2

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• alkynyl substituted α-diazo ketones. Transition metal-catalyzed diazo-decomposition of compound 240 (see Scheme 30) resulted in the formation of metallacyclobutene 241, followed by rapid metallacycloreversion to give carbenoid species 242. Intramolecular cyclopropanation furnished divinylcyclopropane 243

• apply the transition metal catalyzed 1,2-acyl shift with subsequent vinyl carbenoid formation. Propargylic acetate 251 (see Scheme 33) has been shown to undergo 5-exo-dig cyclization via 252 to give zwitterionic intermediate 253. A concomitant fragmentation reaction yielded vinyl-carbenoid 254. Uemura

Multicomponent reactions II

• Thomas J. J. Müller

Beilstein J. Org. Chem. 2014, 10, 115–116, doi:10.3762/bjoc.10.7

• again presents a snap shot of this highly dynamic field. With the traditional formats of letters, full papers, and reviews it spans the broad range of modern chemistry, including organocatalytic, organometallic, transition metal-catalyzed, radical reactions, condensation and isonitrile-based MCR

Triphenylene discotic liquid crystal trimers synthesized by Co₂(CO)₈-catalyzed terminal alkyne [2 + 2 + 2] cycloaddition

• Bin Han,
• Ping Hu,
• Bi-Qin Wang,
• Carl Redshaw and
• Ke-Qing Zhao

Beilstein J. Org. Chem. 2013, 9, 2852–2861, doi:10.3762/bjoc.9.321

• DLC oligomers can be divided into conventional organic reactions and transition metal-catalyzed synthetic methods. The use of transition metal-mediated reactions for constructing new organic functional materials is more efficient and therefore attractive. Our group has embarked upon a program to use

• synthesis of discotic oligomers [46][47][48][49][50]. The transition metal-catalyzed [2 + 2 + 2] cycloaddition of three alkynes for the synthesis of polysubstituted benzene derivatives was studied due to its high efficiency and atomic efficiency [51]. The use of Co2(CO)8 as a catalyst has been extensively

The renaissance of organic radical chemistry – deja vu all over again

• Corey R. J. Stephenson,
• Armido Studer and
• Dennis P. Curran

Beilstein J. Org. Chem. 2013, 9, 2778–2780, doi:10.3762/bjoc.9.312

• homolytic aromatic substitution (BHAS) [3], b) photoredox catalysis [4][5][6][7][8], c) redox chemistry using Bu4NI in combination with t-BuOOH [9], d) transition metal catalyzed processes where radicals are suggested to interact directly with copper, nickel, zinc, palladium, gold and so on [10][11][12][13