Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• acrylates. In the presence of 10 mol % of the catalyst in toluene at room temperature, the [3 + 2] annulations of allenoates with alkenes proceeded smoothly, providing functionalized cyclopentenes in moderate to good yields (up to 87%) with excellent enantioselectivities (87–96% ee) and regioisomeric ratios

• moiety, Shi and co-workers developed an asymmetric [3 + 2] annulation of α-substituted acrylates with an allenoate (Scheme 26) [57]. The reactions proceeded smoothly in toluene at room temperature to give the corresponding functionalized cyclopentenes in high yields with moderate to good ee. The

Investigations of thiol-modified phenol derivatives for the use in thiol–ene photopolymerizations

• Sebastian Reinelt,
• Monir Tabatabai,
• Urs Karl Fischer,
• Norbert Moszner,
• Andreas Utterodt and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1733–1740, doi:10.3762/bjoc.10.180

• ]. Many efforts have been undertaken in the last decades aiming to face and overcome these limitations [1][4][5][6][7][8]. For instance the design of tailored (meth)acrylates based on calix[4]arenes [9][10] or tricyclodecane [11][12] backbones and use of ring-opening monomers as cyclopropane derivatives

N-Alkylated dinitrones from isosorbide as cross-linkers for unsaturated bio-based polyesters

• Oliver Goerz and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 902–909, doi:10.3762/bjoc.10.88

• -dipolar cycloaddition with unsaturated bio-based polyester poly(isosorbide itaconate -co- succinate). Results and Discussion N-Alkylated dinitrones derived from acrylates and crotonates were prepared and evaluated in respect to their 1,3-cycloaddition with itaconic acid containing polyester resins. To

• . Synthesis of Z-configurated model compounds 3a/b from E-benzaldoxime and acrylates 2a/b. Proposed molecular interactions of nitron 3a and dimethyl itaconate (4). 1,3-Dipolaric cycloaddition of nitrones 3a/b with dimethyl itaconate (4). Synthetic route to bio-based dinitrones derived from isosorbide

Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization

• Jacques Lalevée,
• Sofia Telitel,
• Pu Xiao,
• Marc Lepeltier,
• Frédéric Dumur,
• Fabrice Morlet-Savary,
• Didier Gigmes and
• Jean-Pierre Fouassier

Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83

• delivered, e.g., by household lamps and LED bulbs) can be used; this is a catalytic process without loss of efficiency with irradiation. Photopolymerization under sunlight becomes reachable. The production of the radical or cationic initiating species for the FRP of acrylates or the FRPCP of epoxides

• (FRP) of acrylates: The experiments were carried out in laminated conditions or under air. The prepared formulations deposited on a BaF2 pellet (25 µm thick) were irradiated (see the irradiation devices). The evolution of the double bond content was continuously followed by real time FTIR spectroscopy

• ; Scheme 11) [64]. All these described systems, producing radicals, cations or radical cations, allow efficient CP and FRPCP of cationic monomers, FRP of acrylates, simultaneous radical/cationic polymerization of epoxide/acrylate blend. The reactions can be carried out (see in [45][46][47][48][49][50][51

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

• Gijs Koopmanschap,
• Eelco Ruijter and
• Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

Boron-substituted 1,3-dienes and heterodienes as key elements in multicomponent processes

• Ludovic Eberlin,
• Fabien Tripoteau,
• François Carreaux,
• Andrew Whiting and
• Bertrand Carboni

Beilstein J. Org. Chem. 2014, 10, 237–250, doi:10.3762/bjoc.10.19

• also been tested (acrylates, maleic anhydride) giving no products or unsatisfactory results. A large range of aldehydes, as aliphatic, electron-rich or electron-poor benzaldehyde, could be used. Only very hindered aldehydes did not afford any product and both mono- and disubstituted arylhydrazines have

Synthetic scope and DFT analysis of the chiral binap–gold(I) complex-catalyzed 1,3-dipolar cycloaddition of azlactones with alkenes

• María Martín-Rodríguez,
• Luis M. Castelló,
• Carmen Nájera,
• José M. Sansano,
• Olatz Larrañaga,
• Abel de Cózar and
• Fernando P. Cossío

Beilstein J. Org. Chem. 2013, 9, 2422–2433, doi:10.3762/bjoc.9.280

• electrophilic alkenes have not been exploited. Toste´s group published an efficient 1,3-dipolar cycloaddition (1,3-DC) between alanine, phenylalanine and allylglycine derived azlactones with maleimides and acrylates employing dimetallic (S)-Cy-Segphos(AuOBz)2 complex 1 as a catalyst (2 mol %) in the absence of

• unexpected regioselectivity of the 1,3-DC depicted in Scheme 6, calculations within the DFT framework were performed. In the accepted mechanism of the metal catalyzed 1,3-DC of azomethine ylides and acrylates, the α-carbon atom of the azomethine ylide (C2 in Figure 5) reacts with the β-carbon of the acrylate

• this kind of reactive species, the reaction yields cycloadducts possessing a standard regioselectivity in 1,3-DC with acrylates [38]. Since our goal was to understand the origins of the unusual regioselectivity observed in the reaction between dipoles of type Ylide-I with acrylates, trimethylphosphine

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• methods utilising cycloadditions of electron-rich oxazoles and acrylates [17][18] tri- and tetrazines with alkenes/alkynes [19] or pyrones with nitriles [20] have been used successfully to access specifically functionalised pyridines which are difficult to prepare by the more direct condensation routes. A

Gold-catalyzed reaction of oxabicyclic alkenes with electron-deficient terminal alkynes to produce acrylate derivatives

• Yin-wei Sun,
• Qin Xu and
• Min Shi

Beilstein J. Org. Chem. 2013, 9, 1969–1976, doi:10.3762/bjoc.9.233

• reactions is also discussed. Keywords: gold catalysis; oxabicyclic alkenes; substituted acrylates; Introduction Oxabicyclic alkenes are common intermediates in organic synthesis since these compounds can be easily prepared and have a high reactivity for further transformations [1][2][3][4][5][6][7][8

AgOTf-catalyzed one-pot reactions of 2-alkynylbenzaldoximes with α,β-unsaturated carbonyl compounds

• Qiuping Ding,
• Dan Wang,
• Puying Luo,
• Meiling Liu,
• Shouzhi Pu and
• Liyun Zhou

Beilstein J. Org. Chem. 2013, 9, 1949–1956, doi:10.3762/bjoc.9.231

• 1b was treated with acrylonitrile 2h under such conditions, the starting materials were recovered almost completely (Table 1, entry 8). Next, we examined the effect of substituents at the 2-alkynylbenzaldoxime 1. In most cases, 2-alkynylbenzaldoxime 1 reacted with acrylates 2 leading to the desired

• 1a and butyl acrylate (2e). AgOTf-catalyzed one-pot reactions of 2-(p-tolylethynyl)benzaldehyde oxime (1b) with α,β-unsaturated carbonyl compounds 2. One-pot reactions of 2-alkynylbenzaldoximes 1 with acrylates 2. Supporting Information Supporting Information File 410: Experimental part

Organotellurium-mediated living radical polymerization under photoirradiation by a low-intensity light-emitting diode

• Yasuyuki Nakamura and
• Shigeru Yamago

Beilstein J. Org. Chem. 2013, 9, 1607–1612, doi:10.3762/bjoc.9.183

• = 166000, Mw/Mn = 1.15) were also prepared by changing the monomer/1 ratio under LED irradiation through a 50% transmittance ND filter (Table 2, runs 2 and 3). Next, the polymerization of styrene was examined at 90 °C, as the propagation rate constant of styrene is much lower than those of acrylates and

A Lewis acid-promoted Pinner reaction

• Dominik Pfaff,
• Gregor Nemecek and
• Joachim Podlech

Beilstein J. Org. Chem. 2013, 9, 1572–1577, doi:10.3762/bjoc.9.179

• results are obtained with two equivalents of trimethylsilyl triflate as Lewis acid. Good yields are achieved with primary alcohols and aliphatic or benzylic carbonitriles, but the straightforward synthesis of acrylates and benzoates starting with acrylonitrile and benzonitrile, respectively, is similarly

The synthesis of well-defined poly(vinylbenzyl chloride)-grafted nanoparticles via RAFT polymerization

• John Moraes,
• Kohji Ohno,
• Guillaume Gody,
• Thomas Maschmeyer and
• Sébastien Perrier

Beilstein J. Org. Chem. 2013, 9, 1226–1234, doi:10.3762/bjoc.9.139

• particle surface and yields well-defined particles from a range of monomeric precursors [12]. While initial work focussed on common monomers such as styrene [13][14][15] and (meth)acrylates [14][15][16], several recent papers seek to extend this work to a greater variety of monomers [17][18][19][20][21][22

New core-pyrene π structure organophotocatalysts usable as highly efficient photoinitiators

• Sofia Telitel,
• Frédéric Dumur,
• Thomas Faury,
• Bernadette Graff,
• Mohamad-Ali Tehfe,
• Didier Gigmes,
• Jean-Pierre Fouassier and
• Jacques Lalevée

Beilstein J. Org. Chem. 2013, 9, 877–890, doi:10.3762/bjoc.9.101

• . The large choice of Co_Pys should allow for studying the effect of the core on the MO coupling and the resulting absorption properties. The activity of these Co_Py compounds in the FRP of acrylates and the FRPCP (and eventually the cationic polymerization CP) of epoxides through a ring-opening

New simple synthesis of ring-fused 4-alkyl-4H-3,1-benzothiazine-2-thiones: Direct formation from carbon disulfide and (E)-3-(2-aminoaryl)acrylates or (E)-3-(2-aminoaryl)acrylonitriles

• Qiuping Ding,
• Yuqing Lin,
• Guangni Ding,
• Fumin Liao,
• Xiaoyan Sang and
• Yi-Yuan Peng

Beilstein J. Org. Chem. 2013, 9, 460–466, doi:10.3762/bjoc.9.49

• and efficient method to construct ring-fused 4-alkyl-4H-3,1-benzothiazine-2-thione derivatives has been developed from carbon disulfide and (E)-3-(2-aminoaryl)acrylates or (E)-3-(2-aminoaryl)acrylonitriles under mild conditions, without the need for a metal catalyst. The newly developed method

• (Scheme 1) [9]. Promoted by these results, we envisioned that (E)-3-(2-aminoaryl)acrylates or (E)-3-(2-aminoaryl)acrylonitriles could also be utilized as starting substrates for the synthesis of N-heterocycles. Therefore, we focused on the o-amino-α,β-unsaturated compound 1 (Scheme 2), which would be

• hand, we next tested the generality of the (E)-3-(2-aminoaryl)acrylates (Table 2). As expected, a series of functional groups on the phenyl ring of the (E)-butyl 3-(2-aminoaryl)acrylates, such as methyl, chloro, fluoro, and nitro were compatible in this procedure, and the corresponding desired products

Thermotropic and lyotropic behaviour of new liquid-crystalline materials with different hydrophilic groups: synthesis and mesomorphic properties

• Alexej Bubnov,
• Miroslav Kašpar,
• Věra Hamplová,
• Ute Dawin and
• Frank Giesselmann

Beilstein J. Org. Chem. 2013, 9, 425–436, doi:10.3762/bjoc.9.45

• observed for TL5 with respect to that of the chiral acrylates [34]. Quite remarkable observations can be made while comparing the mesomorphic properties of TL2 with those of a compound possessing the same molecular core and chiral centre but differing in the nonchiral chain, i.e., an ethylene glycol unit

Palladium-catalyzed dual C–H or N–H functionalization of unfunctionalized indole derivatives with alkenes and arenes

• Gianluigi Broggini,
• Egle M. Beccalli,
• Andrea Fasana and
• Silvia Gazzola

Beilstein J. Org. Chem. 2012, 8, 1730–1746, doi:10.3762/bjoc.8.198

• indole, furan, and benzofuran rings (Scheme 2) [48]. Working with indole and methyl acrylates in the presence of Pd(OAc)2 and 1,4-benzoquinone in catalytic quantity with tert-butyl hydroperoxide as oxidant, 3-alkenyl-substituted products were obtained. The synthetic value of the direct catalytic C–H

Reactions of nitroxides XIII: Synthesis of the Morita–Baylis–Hillman adducts bearing a nitroxyl moiety using 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl as a starting compound, and DABCO and quinuclidine as catalysts

• Jerzy Zakrzewski

Beilstein J. Org. Chem. 2012, 8, 1515–1522, doi:10.3762/bjoc.8.171

• of biological importance [35][36][37][38][39][40][41][42][43]. The MBH reaction is a rather slow process (complete reaction can take hundreds of hours), especially when acrylates are used [44]. As has been very well known since the 1960s, stable nitroxides can react without affecting the unpaired

• nitroxide moiety on the MBH reaction is unknown. Herein we present the MBH reaction with a nitroxyl radical, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl, used as a starting material as an olefin activated with EWG. Acrylates are considered as rather unreactive in the MBH reaction [44]. It was shown

• that the effects on the reaction of aryl, benzyl, alkyl, and functionalized alkyl acrylic esters with benzaldehyde and furfuraldehyde in the presence of DABCO, strongly depend upon the electronic and steric effects of the ester part. The “unreactivity” of acrylates increases with steric hindrance and

Combined bead polymerization and Cinchona organocatalyst immobilization by thiol–ene addition

• Kim A. Fredriksen,
• Tor E. Kristensen and
• Tore Hansen

Beilstein J. Org. Chem. 2012, 8, 1126–1133, doi:10.3762/bjoc.8.125

• combined in a single step. Vinyl ethers, allyl ethers, acrylates and methacrylates can all be effectively incorporated as part of such thiol–ene networks. The supported organocatalysts have been tried out successfully in several asymmetric transformations, but catalyst recycling so far is relatively poor

Chiral multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita–Baylis–Hillman carbonates with maleimides

• Hong-Ping Deng,
• De Wang,
• Yin Wei and
• Min Shi

Beilstein J. Org. Chem. 2012, 8, 1098–1104, doi:10.3762/bjoc.8.121

• ] annulation catalyzed by chiral phosphines, Zhang and co-workers first reported the asymmetric [3 + 2] annulation of allenoates with acrylates catalyzed by a bicyclic chiral phosphine in 1997 [21]. Moreover, Fu [22][23][24], Marinetti [25][26][27][28], Lu [29][30][31] and other researchers [32][33][34][35][36

Facile isomerization of silyl enol ethers catalyzed by triflic imide and its application to one-pot isomerization–(2 + 2) cycloaddition

• Kazato Inanaga,
• Yu Ogawa,
• Yuuki Nagamoto,
• Akihiro Daigaku,
• Hidetoshi Tokuyama,
• Yoshiji Takemoto and
• Kiyosei Takasu

Beilstein J. Org. Chem. 2012, 8, 658–661, doi:10.3762/bjoc.8.73

• ) cycloaddition of silyl enol ethers with acrylates generating substituted cyclobutanes [10]. We are intrigued that the isomerization of silyl enol ethers and successive (2 + 2) cycloaddition could be promoted by Tf2NH in a one-pot reaction. When 1a was treated with Tf2NH (1 mol %) under the isomerization

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

• substrate presenting two acrylates within the molecule, styrene, and α-methyl styrene (Scheme 1). Reactions with these substrates also afforded the diene products 4–7, in good yields. The anticipated two Heck coupling reactions with the substrate that presents two acrylates, could not be achieved, rather

• . 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

Chiral gold(I) vs chiral silver complexes as catalysts for the enantioselective synthesis of the second generation GSK-hepatitis C virus inhibitor

• María Martín-Rodríguez,
• Carmen Nájera,
• José M. Sansano,
• Abel de Cózar and
• Fernando P. Cossío

Beilstein J. Org. Chem. 2011, 7, 988–996, doi:10.3762/bjoc.7.111

• of acrylates as dipolarophiles has only been explored with the 2-thienyliminoesters 6a. Therefore, based on our experience of silver(I)- and gold(I)-catalyzed 1,3-DC involving azomethine ylides derived from α-iminoester 6b and tert-butyl acrylate, we selected a series of known chiral phosphoramidite

• the approach of the mentioned dipolarophile. Conclusion In this work the complexity of the 1,3-DC reaction of azomethine ylides and dipolarophiles (in this case acrylates) was demonstrated. There are many parameters to control and a small variation can cause a dramatic effect in the overall

• enantiodiscrimination of the process. The temperature does not equally affect silver(I) and gold(I) catalysts. The effect of the heterocycle remains crucial in these transformations because, originally, the enantioselectivity of the reaction between methyl benzylideneiminoglycinate and alkyl acrylates failed in the

Regioselective ester cleavage during the preparation of bisphosphonate methacrylate monomers

• Kamel Chougrani,
• Gilles Niel,
• Bernard Boutevin and
• Ghislain David

Beilstein J. Org. Chem. 2011, 7, 364–368, doi:10.3762/bjoc.7.46

• (meth)acrylates, and can be readily polymerized by emulsion or solution methods [8][9]. Polymers with some phosphonate functionality have long been established as excellent adhesives and anti-corrosion compounds [10][11][12][13][14][15][16][17], however, there has been very little investigation into the

Olefin metathesis in nano-sized systems

• Didier Astruc,
• Abdou K. Diallo,
• Sylvain Gatard,
• Liyuan Liang,
• Cátia Ornelas,
• Victor Martinez,
• Denise Méry and
• Jaime Ruiz

Beilstein J. Org. Chem. 2011, 7, 94–103, doi:10.3762/bjoc.7.13

• terminated by carboxy groups (Scheme 5). These CM reactions were also extended to acrylates that contained a dendronic group. This strategy allowed constructing dendrimers from one generation to the next. Thus, iteration allows synthesizing a dendrimer of second generation with 81 olefin termini from a