Recent advances in the gold-catalyzed additions to C–C multiple bonds

• He Huang,
• Yu Zhou and
• Hong Liu

Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103

• homogeneous gold-catalyzed oxidative cross-coupling which leads to α-arylenones 190 from propargylic acetates 189 and arylboronic acids has been developed by Zhang’s group (Scheme 35) [86]. This cross-coupling reaction reveals the synthetic potential of Au(I)/Au(III) catalytic cycles. Kimber reported a facile

Au(I)/Au(III)-catalyzed Sonogashira-type reactions of functionalized terminal alkynes with arylboronic acids under mild conditions

• Deyun Qian and
• Junliang Zhang

Beilstein J. Org. Chem. 2011, 7, 808–812, doi:10.3762/bjoc.7.92

• , Chinese Academy of Sciences, Ling Ling Road 345 Shanghai 200032 (P. R. China) 10.3762/bjoc.7.92 Abstract A straightforward, efficient, and reliable redox catalyst system for the Au(I)/Au(III)-catalyzed Sonogashira cross-coupling reaction of functionalized terminal alkynes with arylboronic acids under

• cross-coupling, as well as expanding the substrate scope [11][12][13][14]. Various examples have recently been reported for the palladium-catalyzed Sonagashira-type cross-coupling of terminal alkynes with arylboronic acids [13], and the Pd(0)/Pd(II) catalytic cycles have been well studied. Nevertheless

• required [23]. Herein, we report a straightforward, efficient and robust catalyst system for the Sonogashira-type cross-coupling, in which Au(I)/Au(III) catalyzed Csp2–Csp bond formation of terminal alkynes from arylboronic acids under mild conditions. By analogy with other d10 species, Au(I) has the same

Synthesis of chiral mono(N-heterocyclic carbene) palladium and gold complexes with a 1,1'-biphenyl scaffold and their applications in catalysis

• Lian-jun Liu,
• Feijun Wang,
• Wenfeng Wang,
• Mei-xin Zhao and
• Min Shi

Beilstein J. Org. Chem. 2011, 7, 555–564, doi:10.3762/bjoc.7.64

• aryl halides with arylboronic acids were carried out, and it was found that the electronic properties of the R groups and halide atoms significantly affected the reaction yield of the Suzuki–Miyaura reactions. The results have been summarized in Table 1. The [(NHC)Pd(allyl)I] complex 7 was also

The preparation of 3-substituted-1,5-dibromopentanes as precursors to heteracyclohexanes

• Bryan Ringstrand,
• Martin Oltmanns,
• Jeffrey A. Batt,
• Aleksandra Jankowiak,
• Richard P. Denicola and
• Piotr Kaszynski

Beilstein J. Org. Chem. 2011, 7, 386–393, doi:10.3762/bjoc.7.49

• sequence are around 40% [21]. A recently described procedure [32] allows for efficient preparation of 4-aryltetrahydropyrans by the coupling of arylboronic acids and 4-chlorotetrahydropyran in the presence of Ni catalyst (Method 2D). Here, we report the preparation of dibromides 1 having at the 3-position

Air-stable, recyclable, and time-efficient diphenylphosphinite cellulose-supported palladium nanoparticles as a catalyst for Suzuki–Miyaura reactions

• Qingwei Du and
• Yiqun Li

Beilstein J. Org. Chem. 2011, 7, 378–385, doi:10.3762/bjoc.7.48

• catalyst; Suzuki–Miyaura reaction; Introduction The formation of Csp2–Csp2 bonds has long remained a difficult task until the development of the Suzuki–Miyaura palladium-catalyzed reaction [1][2][3]. The palladium-catalyzed Suzuki cross-coupling reaction of aryl halides with arylboronic acids is one of

• catalyst was enough to push the reaction to completion (Table 3, entry 3). To examine the scope for this coupling reaction, a variety of substituted aryl halides were coupled with different arylboronic acids in 95% ethanol in the presence of a catalytic amount of Cell–OPPh2–Pd0 (0.5 mmol % Pd) with K2CO3

• reactivity of aryl bromides was slightly lower than that of the corresponding aryl iodides and in these cases a prolonged time was required. The reaction of aryl chlorides with arylboronic acids was sluggish and gave only small amounts of products in acceptable times. The reusability of the supported

Studies on Pd/NiFe₂O₄ catalyzed ligand-free Suzuki reaction in aqueous phase: synthesis of biaryls, terphenyls and polyaryls

• Sanjay R. Borhade and
• Suresh B. Waghmode

Beilstein J. Org. Chem. 2011, 7, 310–319, doi:10.3762/bjoc.7.41

• arylboronic acids. The reaction gave excellent yields (70–98%) under ligand free conditions in a 1:1 DMF/H2O solvent mixture, in short reaction times (10–60 min). The catalyst could be recovered easily by applying an external magnetic field. The polyaryls were similarly synthesized. Keywords: heterogeneous

• arylboronic acids is one of the most important and powerful methods for the construction of biaryls and polyaryls due to its compatibility towards a wide range of functional groups on both partners [5][6][7][8][9][10]. The resulting Suzuki products have found numerous applications in the synthesis of natural

• short reaction times. Bromobenzene and electron rich aryl bromides required a higher loading of palladium (1.0 mol %) to give comparable results. Both electron rich and electron deficient arylboronic acids gave biaryl products in good to excellent yields. Heterocyclic boronic acids required longer

SbCl₃-catalyzed one-pot synthesis of 4,4′-diaminotriarylmethanes under solvent-free conditions: Synthesis, characterization, and DFT studies

• Ghasem Rezanejade Bardajee

Beilstein J. Org. Chem. 2011, 7, 135–144, doi:10.3762/bjoc.7.19

• can be prepared by the palladium-catalyzed arylation of aryl(azaaryl)methanes with aryl halides [27], cationic Pd(II)/bipyridine-catalyzed addition of arylboronic acids to arylaldehydes [28], and by Friedel–Crafts type catalytic alkylation of aromatic rings with aromatic aldehydes and their imines [29

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

• (IV) triacetates [33] and pentavalent organobismuth reagents [34] have also been used as aryl donors for copper-mediated C–N couplings. Further improvement of N-arylation conditions was achieved by the use of arylboronic acids. The reagents are not sensitive to air; the reaction proceeds at room

• azetidinones 111 with different arylboronic acids 112 to give 113 in nearly quantitative yields (Scheme 26) [77]. The palladium-catalysed N-arylation of 2-azetidinones was only previously described for unsubstituted azetidinones [78]. N-Aryltriazole ribonucleosides 118 with potent anti-proliferative activity

Suzuki–Miyaura cross-coupling reaction of 1-aryltriazenes with arylboronic acids catalyzed by a recyclable polymer-supported N-heterocyclic carbene–palladium complex catalyst

• Guangming Nan,
• Fang Ren and
• Meiming Luo

Beilstein J. Org. Chem. 2010, 6, No. 70, doi:10.3762/bjoc.6.70

• Suzuki–Miyaura cross-coupling reaction of 1-aryltriazenes with arylboronic acids catalyzed by a recyclable polymer-supported Pd–NHC complex catalyst has been realized for the first time. The polymer-supported catalyst can be re-used several times still retaining high activity for this transformation

• , arylsulfonyl chlorides and arenediazonium salts with arylboronic acids that gave biaryls in good to excellent yields [28][31][32]. As part of our ongoing investigations aimed at the development of transition metal catalysis, we report here that the Suzuki–Miyaura cross-couplings of 1-aryltriazenes with

• arylboronic acids can be readily effected with our polystyrene-supported Pd–NHC catalyst, which shows high efficiency and can be easily recovered and reused several times still retaining high activity. Results and Discussion The polystyrene-supported Pd–NHC catalyst 1 was prepared according to our reported

Continuous flow enantioselective arylation of aldehydes with ArZnEt using triarylboroxins as the ultimate source of aryl groups

• Julien Rolland,
• Xacobe C. Cambeiro,
• Carles Rodríguez-Escrich and
• Miquel A. Pericàs

Beilstein J. Org. Chem. 2009, 5, No. 56, doi:10.3762/bjoc.5.56

• the expensive Ph2Zn by other, more convenient, aryl sources. To this end, the use of arylboron species has provided particularly good results. In contrast to what happens with diarylzinc reagents, a wide variety of arylboronic acids are commercially available at a convenient price, and these species

• the initial reaction with the boronic acid (Scheme 1). On the other hand, triarylboroxins, easily prepared from the corresponding arylboronic acids by thermally induced dehydration under vacuum, have recently been applied with success as the starting materials for the preparation of the ArZnEt species

Regioselective alkynylation followed by Suzuki coupling of 2,4-dichloroquinoline: Synthesis of 2-alkynyl- 4-arylquinolines

• Ellanki A. Reddy,
• Aminul Islam,
• K. Mukkanti,
• Venkanna Bandameedi,
• Dipal R. Bhowmik and
• Manojit Pal

Beilstein J. Org. Chem. 2009, 5, No. 32, doi:10.3762/bjoc.5.32

• derivatives earlier [7][8][9][10][11][12][13][14][15][16][17]. Next, in order to prepare 2-alkynyl-4-arylquinolines (5) we planned to exploit the reactivity of chloro group of 3 towards Suzuki arylation reaction. Accordingly, a variety of arylboronic acids were coupled with 3 and results of this study are

• summarized in Table 2. The Suzuki reaction was carried out using arylboronic acids in the presence of (PPh3)2PdCl2 as a catalyst, CsCO3 as a base, tricyclohexyl phophine, (PCy3) as a ligand in dioxane–water at 80 °C. The arylboronic acids used in this reaction include phenylboronic acid (entries 1–6, Table 2

• of 2,4-dichloroquinoline at C-2 position. The 2-alkynyl-4-chloroquinolines 3 thus formed then undergo Suzuki reaction in the next step. Oxidative addition of Pd0 generated in situ to compound 3 followed by trans-organometallation of the resultant aryl-palladium complex formed with arylboronic acids

N-Arylation of amines, amides, imides and sulfonamides with arylboroxines catalyzed by simple copper salt/EtOH system

• Zhang-Guo Zheng,
• Jun Wen,
• Na Wang,
• Bo Wu and
• Xiao-Qi Yu

Beilstein J. Org. Chem. 2008, 4, No. 40, doi:10.3762/bjoc.4.40

• arylation reaction using arylboronic acids as aryl donors was discovered by Chan, Evans and Lam independently [5][6][7]. Based on these studies, further improvements to the catalytic variation of organoboron compounds cross coupling have been reported. Among these organoboron compounds, arylboronic acids

• arylboronic acids in protic solvent system had been developed in our previous reports [16][17]. Similar catalytic systems using non-halogenated hydrocarbon solvents have also been reported by Kantam and Prakash [18][19]. However, these procedures require an atmosphere of air or O2 and the use of high

• arylboronic acids in good yields in methanol at room temperature using copper-exchanged fluorapatite [20]. However, copper-exchanged fluorapatite is a composite salt prepared by a complex, elaborate procedure and has several limitations for the further application. There has been considerable interest