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

• ; recyclable catalyst; Suzuki–Miyaura reaction; Introduction The unsymmetrical biaryls feature in a diverse range of organic compounds, such as natural products, advanced materials, liquid crystals, ligands and molecules of medicinal interest [1][2][3][4]. The palladium-catalyzed Suzuki–Miyaura cross-coupling

• reaction has evolved as a powerful synthetic tool for the synthesis of unsymmetrical biaryls in both academic laboratories and industry [5][6][7][8]. Most of the reported Suzuki–Miyaura reactions are based on the use of aryl halides and triflates, and recently sulfonates and carboxylates, as the

A short and efficient synthesis of valsartan via a Negishi reaction

• Samir Ghosh,
• A. Sanjeev Kumar and
• G. N. Mehta

Beilstein J. Org. Chem. 2010, 6, No. 27, doi:10.3762/bjoc.6.27

• synthesis of sartans: whilst the synthesis of losartan [4] as described in the literature makes use of Negishi [5][6] and Ullmann [7] couplings, the published methods for the preparation of valsartan utilize Suzuki–Miyaura couplings [8]. Of these, Negishi reactions have proved to be very efficient. However

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

• KF-loaded aluminas is available in the literature, there is almost no data concerning the influence of parameters such as alumina modification or KF-loading on experimental results. Hence, the Pd-catalyzed, solvent-free Suzuki–Miyaura reaction was chosen as model reaction to investigate the effect of

• applied in solvent-free Pd-catalyzed Suzuki–Miyaura cross-coupling reactions of aryl bromides with phenylboronic acid, and the performances of the individual SRS were compared [33][34][36][37][38][39][40][41][42]. Results and Discussion Incorporation of KF–Al2O3 as a basic component in organic synthesis

• pH measurements of aqueous suspension of the pure aluminas. Investigating the influence of different SRS, the Pd(OAc)2-assisted Suzuki–Miyaura coupling of phenylboronic acid (1) with different aryl bromides 2 furnishing p-substituted biphenyls 3 (Scheme 1) was chosen. Reactions were performed in a

Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

• Susan Kelleher,
• Pierre-Yves Quesne and
• Paul Evans

Beilstein J. Org. Chem. 2009, 5, No. 69, doi:10.3762/bjoc.5.69

• above proving inefficient, palladium chemistry was subsequently considered. The vinyl bromide 24a was reported to participate in Sonagashira alkynylation chemistry; however, yields of the resultant enyne were low [20]. Therefore, we decided to investigate Suzuki–Miyaura cross-coupling reaction as a

• . Possible explanation for the products formed in the dibromination of 5a and 5b. Lithiation–CO2 quench approach for the synthesis of 26 from vinyl bromide 24a. Suzuki–Miyaura cross-coupling of 24a and the diastereoselective hydrogenation of the resultant styrene adducts. Attempted sulfonamide double

Gold film- catalysed benzannulation by Microwave- Assisted, Continuous Flow Organic Synthesis (MACOS)

• Gjergji Shore,
• Michael Tsimerman and
• Michael G. Organ

Beilstein J. Org. Chem. 2009, 5, No. 35, doi:10.3762/bjoc.5.35

• Suzuki–Miyaura and Heck reactions, i.e., Pd-thin films promote these transformations without any additional catalyst being added to the reactant stream(s) that enter the flow tube [28]. Without microwave irradiation, the above-described cross-coupling reactions did not proceed indicating that there is

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

• heterogeneous supports for palladium(0) nanoparticles is described. These functionalized polymers were incorporated inside a flow reactor and employed in Suzuki–Miyaura and Heck cross couplings under continuous flow conditions. Keywords: Heck–Mizoroki reaction; heterogeneous catalysis; ion exchange resin

• ; microreactor; monolith; palladium; Suzuki–Miyaura reaction; Introduction Functionalized solid supports like polymers loaded with homogeneous catalysts are well established in organic synthesis [1][2][3][4]. Simple purification of the products and easy recyclability of the catalysts are major advantages of

• nanoparticles (7–10 nm in size and a palladium content of 0.03 weight% Pd on polyionic polymer). Suzuki–Miyaura cross coupling reactions In our earlier work we showed that these materials are well suited for transfer hydrogenations under flow conditions [23][24]. Recently, the Suzuki–Miyaura reaction and other

Oxidative cyclization of alkenols with Oxone using a miniflow reactor

• Yoichi M. A. Yamada,
• Kaoru Torii and
• Yasuhiro Uozumi

Beilstein J. Org. Chem. 2009, 5, No. 18, doi:10.3762/bjoc.5.18

• laminar flow interface [16], resulting in the instantaneous production of biaryls (quantitative yield within 4 s of residence time) via a palladium-catalyzed Suzuki-Miyaura reaction under microflow conditions. An additional advantage of micro- and minireactors is the small heat capacity of the micro- and

Convenient methods for preparing π-conjugated linkers as building blocks for modular chemistry

• Jiří Kulhánek,
• Filip Bureš and
• Miroslav Ludwig

Beilstein J. Org. Chem. 2009, 5, No. 11, doi:10.3762/bjoc.5.11

• use as building blocks in Suzuki–Miyaura or Sonogashira coupling reactions. Keywords: boronic acid; donor/acceptor; linker; Sonogashira reaction; property tuning; push-pull; Suzuki–Miyaura reaction; Introduction Development of new organic compounds with improved and advanced properties is one of the

• moieties is usually accomplished by cross-coupling reactions, in particular by the Suzuki–Miyaura [26][27] or the Sonogashira [28] reactions. Consequently, the availability of the suitably substituted π-conjugated linkers of various lengths bearing boronic ester functionality or terminal acetylene is

• crucial for such a synthetic approach. Hence, we report here a convenient synthesis as well as characterization of either unsubstituted (R = H) or donor substituted (R = NMe2, OMe) π-conjugated linkers designed for the Suzuki–Miyaura and Sonogashira cross-couplings with a systematically varied and

Mechanistic aspects of the isomerization of Z-vinylic tellurides double bonds in the synthesis of potassium Z-vinyltrifluoroborate salts

• Hélio A. Stefani,
• Rafael C. Guadagnin,
• Artur F. Keppler,
• Giancarlo V. Botteselle,
• João V. Comasseto and
• Carlos A. Suganuma

Beilstein J. Org. Chem. 2008, 4, No. 9, doi:10.1186/1860-5397-4-9

• acids and boronate esters are the most commonly used derivatives in Suzuki-Miyaura cross-coupling reactions. Recently, Molander et al. [1] and our group [2] have explored the use of potassium organotrifluoroborate salts as an alternative to the usual organoboron reagents in alkenyl-alkenyl [3], aryl