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

• -catalyzed reactions [125]. One of the first examples of a rhodium-catalyzed asymmetric 1,4-addition of lactams was reported by Hayashi and co-workers [136]. They reported that the key to achieving high yields for this reaction was to use arylboroxines instead of arylboronic acids and the addition of 1 equiv

A novel 4-aminoantipyrine-Pd(II) complex catalyzes Suzuki–Miyaura cross-coupling reactions of aryl halides

• Claudia A. Contreras-Celedón,
• Darío Mendoza-Rayo,
• José A. Rincón-Medina and
• Luis Chacón-García

Beilstein J. Org. Chem. 2014, 10, 2821–2826, doi:10.3762/bjoc.10.299

• are tolerated. Keywords: 4-aminoantipyrine; arylboronic acids; biaryls; cross-coupling; palladium(II) complex; Introduction The sp2–sp2 carbon–carbon bond formation through cross-coupling reactions catalyzed by metal complexes has emerged as a powerful tool in organic synthesis [1][2][3][4][5][6

• organic reactions. Synthesis of 4-aminoantipyrine-Pd(II) complex. Reaction of different aryl halides with substituted arylboronic acids. Reaction conditions: phenylboronic acid (0.40 mmol), aryl halide (0.27 mmol), 4-AAP–Pd(II) (0.3 mol %), 2 M K2CO3 (0.67 mmol), ethanol (2 mL), heating under reflux for 4

Aryl substitution of pentacenes

• Andreas R. Waterloo,
• Anna-Chiara Sale,
• Dan Lehnherr,
• Frank Hampel and
• Rik R. Tykwinski

Beilstein J. Org. Chem. 2014, 10, 1692–1705, doi:10.3762/bjoc.10.178

• opportunity to vary the pendent substituent through a Pd-catalyzed cross-coupling protocol (Scheme 2). Thus, pentacene 3g was treated under Suzuki–Miyaura coupling conditions with arylboronic acids, and the desired pentacenes 3j,k were obtained in yields of 92 and 68%, respectively. Notably, anthracenyl

Stereoselective synthesis of carbocyclic analogues of the nucleoside Q precursor (PreQ₀)

• Sabin Llona-Minguez and
• Simon P. Mackay

Beilstein J. Org. Chem. 2014, 10, 1333–1338, doi:10.3762/bjoc.10.135

• introduction of diverse aryl groups at the 3-position of the cyclohexane ring using commercially available arylboronic acids as building blocks, and Pd catalysis to form the new C–C bond, followed by a highly diastereoselective ketone-to-amine conversion. Others have reported on similar preparations of 3

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

• -(aryl)arylphosphonic acid monoethyl esters were efficiently prepared by a Suzuki reaction of 2-bromoiodoarenes with arylboronic acids, a lithium bromide exchange reaction of 2-bromobiaryls followed by diethylphosphinylation with diethyl chlorophosphate, and the C–O cleavage of diethyl 2-(aryl

Palladium-catalysed cross-coupling reaction of ultra-stabilised 2-aryl-1,3-dihydro-1H-benzo[d]1,3,2-diazaborole compounds with aryl bromides: A direct protocol for the preparation of unsymmetrical biaryls

• Siphamandla Sithebe and
• Ross S. Robinson

Beilstein J. Org. Chem. 2014, 10, 1107–1113, doi:10.3762/bjoc.10.109

• cross-coupling; Introduction Arylboronic acids 1, arylboronate esters 2 and potassium aryltrifluoroborate salts 3 (Figure 1) have received considerable attention and have found a special place as mild and versatile nucleophilic coupling partners for carbon–carbon bond-forming cross-coupling reactions

• counterpart (13e) only affording the coupled products in moderate yields (Table 3, entries 9–11). Conclusion Although arylboronic acids, arylboronate esters and potassium aryltrifluoroborate salts are powerful coupling partners in the Suzuki–Miyaura cross-coupling realm, extending the scope of organoboron

• Siphamandla Sithebe Ross S. Robinson Warren Laboratory, School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa 10.3762/bjoc.10.109 Abstract There has been a significant interest in organoboron compounds such as arylboronic

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

A new manganese-mediated, cobalt-catalyzed three-component synthesis of (diarylmethyl)sulfonamides

• Antoine Pignon,
• Erwan Le Gall and
• Thierry Martens

Beilstein J. Org. Chem. 2014, 10, 425–431, doi:10.3762/bjoc.10.39

• -supported benzotriazole [7] with arylmagnesium reagents, addition of phenyllithium to selenoamides [8], addition of organometallic species [9][10][11][12][13][14][15][16][17][18][19][20][21] or arylboronic acids [22][23][24][25][26][27] to imines, reaction of organolithium and Grignard reagents with

Cu-Mediated trifluoromethylation of benzyl, allyl and propargyl methanesulfonates with TMSCF₃

• Xueliang Jiang and
• Feng-Ling Qing

Beilstein J. Org. Chem. 2013, 9, 2862–2865, doi:10.3762/bjoc.9.322

• -mediated trifluoroethylation of arylboronic acids [13][14] (Scheme 1a) and trifluoromethylation of benzyl halides [15][16][17][18][19][20][21] (Scheme 1b) are more convenient. Especially trifluoromethylations of benzyl bromides with a [CuCF3] species, which are generated from different precursors, are

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

• hydroamination intermediate affording tricyclic 3-benzazepines 129 (Scheme 32c). In the same field, Zhang reported the carboamination, carboalkoxylation and carbolactonization of terminal alkenes with arylboronic acids. Under best conditions, oxidative gold catalysis provided expedient access to various

• first example of C–H functionalization by alkylgold intermediates. The optimized conditions required the use of the electrophilic complex [(p-CF3Ph)3PAuNTf2] and 30 equivalents of water, in order to increase the solubility of Selectfluor in THF. Heteroarylation of alkenes with arylboronic acids under

• ]. The reaction took place under mild conditions and exhibited a wide substrate scope, being highly tolerant towards a number of olefins, arylboronic acids and nucleophiles. In particular, primary, secondary, tertiary alcohols and even water could be employed as nucleophiles, affording the corresponding

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

• . M. S. Sanford has developed a mild and general approach for the Cu-catalyzed/Ru-photocatalyzed trifluoromethylation and perfluoroalkylation of arylboronic acids [96]. The ruthenium-bipyridyl complex plays a double role in this reaction, namely the generation of the CF3 radical, and the oxidation of

Consecutive cross-coupling reactions of 2,2-difluoro-1-iodoethenyl tosylate with boronic acids: efficient synthesis of 1,1-diaryl-2,2-difluoroethenes

• Ju Hee Kim,
• Su Jeong Choi and
• In Howa Jeong

Beilstein J. Org. Chem. 2013, 9, 2470–2475, doi:10.3762/bjoc.9.286

• the consecutive cross-coupling reaction of the 2,2-difluoro-1-bromoethenylzinc reagent with aryl iodides, followed by arylboronic acids [17]. Recently, we also prepared 2,2-difluoro-1-tributylstannylethenyl tosylate and (2,2-difluoroethenylidene)bis(tributylstannane) which were utilized in the

• 2,2,2-trifluoroethyl tosylate (1) with 2 equiv of LDA in THF at −78 °C, followed by treatment with 1 equiv of iodine (Scheme 1). First, we attempted the consecutive palladium-catalyzed cross-coupling reaction of 2 with different arylboronic acids to afford unsymmetrical 1,1-diaryl-2,2-difluoroethenes

• with other arylboronic acids bearing a proton, fluoro, chloro, methyl, methoxy and trifluoromethyl on the ortho-, meta- or para-position of the benzene ring. Reactions were successful with both electron-donating and electron-withdrawing arylboronic acids to produce the corresponding 2,2-difluoro-1

An easy direct arylation of 5-pyrazolones

• Hao Gong,
• Yiwen Yang,
• Zechao Wang and
• Chunxiang Kuang

Beilstein J. Org. Chem. 2013, 9, 2033–2039, doi:10.3762/bjoc.9.240

• synthesize a new series of heterocyclic compounds containing the pyrazolone moiety. The reaction of pyrazolones with arylboronic acids is an attractive approach for the synthesis of arylpyrazolone [15][16]. However, it often needs pre-formation of halo-pyrazolones. Transition metal-catalyzed direct arylation

Acid, silver, and solvent-free gold-catalyzed hydrophenoxylation of internal alkynes

• Marcia E. Richard,
• Daniel V. Fraccica,
• Kevin J. Garcia,
• Erica J. Miller,
• Rosa M. Ciccarelli,
• Erin C. Holahan,
• Victoria L. Resh,
• Aakash Shah,
• Peter M. Findeis and
• Robert A. Stockland Jr.

Beilstein J. Org. Chem. 2013, 9, 2002–2008, doi:10.3762/bjoc.9.235

• prepared by displacement of dimethyl sulfide from Me2SAuCl by JohnPhos or t-BuXPhos [23][24]. The (NHC)AuCl (NHC = SIMes, IMes, SIPr, IPr) [19][25] precursors as well as arylgold compounds 1–3 [14] were prepared following literature procedures. The arylboronic acids, alkynes, phenols, and Cs2CO3 (powder

A scalable synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand

• Hideki Shimizu,
• Jeffrey C. Holder and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2013, 9, 1637–1642, doi:10.3762/bjoc.9.187

• ][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Recently, our laboratory reported the catalytic asymmetric conjugate addition of arylboronic acids to cyclic, β,β-disubstituted enones utilizing (S)-t-BuPyOx (1) as the chiral ligand (Figure 1) [24]. This robust reaction is

Palladium(II)-catalyzed Heck reaction of aryl halides and arylboronic acids with olefins under mild conditions

• Tanveer Mahamadali Shaikh and
• Fung-E Hong

Beilstein J. Org. Chem. 2013, 9, 1578–1588, doi:10.3762/bjoc.9.180

• of arylboronic acids with olefins, which were catalyzed by Pd(OAc)2 and employed N-bromosuccinimide as an additive under ambient conditions. The resulted biaryls have been obtained in moderate to good yields. Keywords: aryl halides; Heck reaction; olefins; palladium-complex; phosphine; Introduction

• the synthesis of leading molecules, a variety of preparative methodologies have been developed. Particularly, the Heck reaction is one of the most chosen methods in the synthesis of aryl-substituted olefins [7][8][9]. Aryl halides or arylboronic acids are among the most commonly employed arylpalladium

• catalyzed cross-coupling of aryl halides 1 with olefins 2 at 60 °C; and (ii) Pd(OAc)2 catalyzed arylation of arylboronic acids 4 with olefins at 25 °C (Scheme 1). Results and Discussion Heck reaction of aryl halides with olefins In the presence of solvents, secondary phosphine oxide (RR'P(O)H) might undergo

Coupling of C-nitro-NH-azoles with arylboronic acids. A route to N-aryl-C-nitroazoles

• Marta K. Kurpet,
• Aleksandra Dąbrowska,
• Małgorzata M. Jarosz,
• Katarzyna Kajewska-Kania,
• Nikodem Kuźnik and
• Jerzy W. Suwiński

Beilstein J. Org. Chem. 2013, 9, 1517–1525, doi:10.3762/bjoc.9.173

• Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, Zabrze 41-819, Poland 10.3762/bjoc.9.173 Abstract A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between variously substituted arylboronic acids and 3(5)-nitro-1H-pyrazole catalyzed by copper salt has

• . Keywords: arylboronic acids; C-nitroazoles; coupling; N-arylation; N-aryl-C-nitroazoles; Introduction The nitroazoles constitute a class of compounds with a broad spectrum of useful properties. They have found applications in agrochemicals as plant-growth regulators [1], herbicides or insecticides [2], in

• arylboronic acids and substituted C-nitroazole coupling, applying the conditions described for the Chan–Lam reaction. This involves the use of chlorinated solvents, pyridine as base, and prolonged reaction times to obtain high yields of the product [28][29]. No detailed investigation on the influence of the

Synthesis and structure of trans-bis(1,4-dimesityl-3-methyl-1,2,3-triazol-5-ylidene)palladium(II) dichloride and diacetate. Suzuki–Miyaura coupling of polybromoarenes with high catalytic turnover efficiencies

• Jeelani Basha Shaik,
• Venkatachalam Ramkumar,
• Babu Varghese and
• Sethuraman Sankararaman

Beilstein J. Org. Chem. 2013, 9, 698–704, doi:10.3762/bjoc.9.79

• polybromoarenes using complex 1. Multiple Suzuki–Miyaura coupling of polybromoarenes with arylboronic acids by using complex 1a. Supporting Information Supporting Information File 116: Spectroscopic characterization data of compounds 8, 10, 11, 13, 15, 17, 22, 24 and 27. Supporting Information File 117: CIF file

Arylglycine-derivative synthesis via oxidative sp³ C–H functionalization of α-amino esters

• Zhanwei Xu,
• Xiaoqiang Yu,
• Xiujuan Feng and
• Ming Bao

Beilstein J. Org. Chem. 2012, 8, 1564–1568, doi:10.3762/bjoc.8.178

•  1, reactions 1–3). However, these reactions need expensive arylboronic acids (Petasis reaction) [4][5][6][7][8][9] and suitable leaving groups [10][11][12] as well as a metal catalyst (Polonovsky reaction; this route requires the preparation of amine N-oxide in advance) [13][14]. We have recently

Palladium-catalyzed substitution of (coumarinyl)methyl acetates with C-, N-, and S-nucleophiles

• Kalicharan Chattopadhyay,
• Erik Fenster,
• Alexander J. Grenning and
• Jon A. Tunge

Beilstein J. Org. Chem. 2012, 8, 1200–1207, doi:10.3762/bjoc.8.133

• chemical library synthesis. Thus, we chose to investigate the Pd-catalyzed benzylic substitution reaction of (coumarinyl)methyl acetates with various nucleophiles. In the forthcoming sections, the coupling of this coumarin template to arylboronic acids [56][57][58][59][60][61], amines [47] and

• -like coupling reaction of (coumarinyl)methyl acetate and arylboronic acids, we screened reaction conditions for the coupling of coumarin 1a with phenylboronic acid (Table 2). We were pleased to find that the reaction progressed reasonably well to 3a under various conditions. For example, inorganic

Aryl nitrile oxide cycloaddition reactions in the presence of pinacol boronic acid ester

• Sarah L. Harding,
• Sebastian M. Marcuccio and
• G. Paul Savage

Beilstein J. Org. Chem. 2012, 8, 606–612, doi:10.3762/bjoc.8.67

• convenient substrate would be the arylboronate nitrile oxide 1, which would undergo 1,3-dipolar cycloaddition to give isoxazolines 2. This latter compound could in turn be coupled with heterocycles or aryl groups to give insecticidal [5] derivatives of type 3 (Scheme 1). The utility of arylboronic acids and

Branching out at C-2 of septanosides. Synthesis of 2-deoxy-2-C-alkyl/aryl septanosides from a bromo-oxepine

• Supriya Dey and
• Narayanaswamy Jayaraman

Beilstein J. Org. Chem. 2012, 8, 522–527, doi:10.3762/bjoc.8.59

• . Conclusion The present study illustrates the effective application of synthetically useful bromo-oxepine for the preparation of hitherto unknown 2-deoxy-2-C-alkyl/aryl septanoside derivatives. C–C bond forming Heck, Suzuki and Sonogashira coupling reactions, with appropriate acrylates, arylboronic acids and

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

• key activation step of the benzoxazole by the arylpalladium complex, produced by a well-established silver-catalyzed decarboxylative palladation reaction. As its second role, the Ag(II) salt serves as a reoxidizing agent (Scheme 26b) [74]. Recently, arylsilanes and arylboronic acids were also proposed

• with arylboronic acids providing the arylazolylpalladium complex, which delivers the product (Scheme 27b and Scheme 28b). Rhodium- and nickel-catalyzed direct arylation of oxazoles with halides The methodology for the Rh(I)-catalyzed direct substitutive coupling of azoles with halides was developed by

• )-catalyzed direct arylation of benzoxazole with arylboronic acids [76]; (a) procedure; (b) proposed mechanism. Ni(II)-catalyzed direct arylation of benzoxazoles with arylboronic acids under O2 [76]; (a) procedure; (b) proposed mechanism. Rhodium-catalyzed direct arylation of benzoxazole [78][79]. Ni(II

Scaling up of continuous-flow, microwave-assisted, organic reactions by varying the size of Pd-functionalized catalytic monoliths

• Ping He,
• Stephen J. Haswell,
• Paul D. I. Fletcher,
• Stephen M. Kelly and
• Andrew Mansfield

Beilstein J. Org. Chem. 2011, 7, 1150–1157, doi:10.3762/bjoc.7.133

• demonstrated by Uozumi et al. [11], where carbon–carbon bond forming reactions of aryl halides and arylboronic acids under microflow conditions can be achieved quantitatively within 4 s residence time. However, the stability of the catalytic membrane was not discussed. Monolith based devices have shown good