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Search for "addition reactions" in Full Text gives 162 result(s) in Beilstein Journal of Organic Chemistry.

Catalytic asymmetric synthesis of biologically important 3-hydroxyoxindoles: an update

  • Bin Yu,
  • Hui Xing,
  • De-Quan Yu and
  • Hong-Min Liu

Beilstein J. Org. Chem. 2016, 12, 1000–1039, doi:10.3762/bjoc.12.98

Graphical Abstract
  • same group reported the organocatalytic asymmetric addition reactions of isatins with electron-rich aromatics sesamols using the cinchona alkaloid-derived thiourea catalyst (cat. 17) under mild conditions. In the presence of 10% catalyst, sesamols reacted with isatins smoothly in tert-butyl ether at
  • corresponding (R)-3-aryl-3-hydroxyoxindoles in good yields (up to 87% yield) and with excellent enantioselectivity (up to 92% ee, Scheme 31) [48]. This slightly modified protocol was then successfully applied to the addition reactions of 1-naphthols and isatins, affording the desired products in slightly lower
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Published 18 May 2016

1H-Imidazol-4(5H)-ones and thiazol-4(5H)-ones as emerging pronucleophiles in asymmetric catalysis

  • Antonia Mielgo and
  • Claudio Palomo

Beilstein J. Org. Chem. 2016, 12, 918–936, doi:10.3762/bjoc.12.90

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  • )-ones 1 as pronucleophiles in organocatalyzed Michael addition reactions 2-Thio-1H-imidazol-4(5H)-ones 1 (R = SBn) have been reported to be effective equivalents of N-subtituted (alkyl, aryl, allyl) α-amino acids in conjugate addition reactions to both, nitroalkenes and α-silyloxy enones as Michael
  • reactions. 2.2.1 Michael addition reactions, nitroalkenes as acceptors. The first example of the utility of the thiazol-4(5H)-ones 2 as pronucleophiles in asymmetric catalysis was reported in 2013 in the Michael addition to nitroalkenes catalyzed by the bifunctional ureidopeptide-like Brønsted base C5
  • . Chiral phosphine-mediated nucleophilic catalysis has attracted considerable attention in the recent years [98][99][100][101]. However, few examples of phosphine-mediated γ-addition reactions have been reported. Pioneering studies on γ-additions of pronucleophiles to allenoates or alkynoates were first
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Published 09 May 2016

Asymmetric α-amination of 3-substituted oxindoles using chiral bifunctional phosphine catalysts

  • Qiao-Wen Jin,
  • Zhuo Chai,
  • You-Ming Huang,
  • Gang Zou and
  • Gang Zhao

Beilstein J. Org. Chem. 2016, 12, 725–731, doi:10.3762/bjoc.12.72

Graphical Abstract
  • a variety of reactions such as aza-Morita–Baylis–Hillman reactions [19][20][21], Rauhut–Currier reactions [22][23][24][25][26][27], Michael addition reactions [28][29][30][31][32][33][34][35], and various cycloadditions [36][37][38][39]. In recent years, our group has focused on the development of
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Published 15 Apr 2016

Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

  • Laura A. Bryant,
  • Rossana Fanelli and
  • Alexander J. A. Cobb

Beilstein J. Org. Chem. 2016, 12, 429–443, doi:10.3762/bjoc.12.46

Graphical Abstract
  • set up a 4π-electrocyclization, generating second intermediate 27. Elimination of the tertiary amine then gives γ-methylene cyclopentenone 28. 1,2-Addition reactions Henry reaction The use of cupreine and cupreidine derivatives in the addition of nitroalkanes to carbonyl compounds was first
  • nitroolefins, and (b) Lin’s similar process with α-nitroesters using the symmetric hydrocupreidine system HCPD-44. A diastereodivergent sulfa-Michael addition developed by Melchiorre and co-workers. Melchiorre’s vinylogous Michael addition. Simpkins’s TKP conjugate addition reactions. Hydrocupreine catalyst
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Published 07 Mar 2016

A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates

  • Hong-Bo Zhang,
  • Yong-Chun Luo,
  • Xiu-Qin Hu,
  • Yong-Min Liang and
  • Peng-Fei Xu

Beilstein J. Org. Chem. 2016, 12, 253–259, doi:10.3762/bjoc.12.27

Graphical Abstract
  • trifluoroacetic anhydride in DCM (Scheme 2). Finally, we propose a mechanism for the reaction. Initially, substrate 1 is activated by catalyst (I), which reacts with substrate 2 via two Michael addition reactions to sequentially produce II and III. Then, IV is generated from III by an aldol reaction. Finally, the
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Published 11 Feb 2016

Copper-catalyzed asymmetric conjugate addition of organometallic reagents to extended Michael acceptors

  • Thibault E. Schmid,
  • Sammy Drissi-Amraoui,
  • Christophe Crévisy,
  • Olivier Baslé and
  • Marc Mauduit

Beilstein J. Org. Chem. 2015, 11, 2418–2434, doi:10.3762/bjoc.11.263

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  • -selective ACA reactions with enynones. Linear dienones as substrates in 1,4-asymmetric conjugate addition reactions of Grignard reagents catalyzed by a copper-based system. 1,4-ACA of trimethylaluminium to a cyclic enynone catalyzed by a copper-NHC system. Generation of a sterically encumbered chiral
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Published 03 Dec 2015

Copper-catalyzed arylation of alkyl halides with arylaluminum reagents

  • Bijay Shrestha and
  • Ramesh Giri

Beilstein J. Org. Chem. 2015, 11, 2400–2407, doi:10.3762/bjoc.11.261

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  • form triorganoaluminate species in the presence of anions in solution [52][53][54][55][56][57]. In addition, organoaluminum reagents have been demonstrated to undergo transmetalation with Cu salts based on their participation in allylic and conjugate addition reactions [11][15][43]. Similar Cu
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Published 02 Dec 2015

Two strategies for the synthesis of the biologically important ATP analogue ApppI, at a multi-milligram scale

  • Janne Weisell,
  • Jouko Vepsäläinen and
  • Petri A. Turhanen

Beilstein J. Org. Chem. 2015, 11, 2189–2193, doi:10.3762/bjoc.11.237

Graphical Abstract
  • isopentenyl group to addition reactions under mild reaction conditions [8] combined with the sensitivity of the two P–O–P bridges for hydrolysis. These points may explain at least partly the quite low 14% isolated yields for ApppI we reported in this paper. Conclusion In conclusion, two feasible methods to
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Published 13 Nov 2015

Synthesis of constrained analogues of tryptophan

  • Elisabetta Rossi,
  • Valentina Pirovano,
  • Marco Negrato,
  • Giorgio Abbiati and
  • Monica Dell’Acqua

Beilstein J. Org. Chem. 2015, 11, 1997–2006, doi:10.3762/bjoc.11.216

Graphical Abstract
  • reactivity upon specific substitution patterns at the indole nucleus were observed by us in competitive Diels–Alder cycloaddition/Michael addition reactions of vinylindoles with classical dienophile and in competitive cycloaddition/hydroarylation reactions with allenes, see [20][21] for a more detailed
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Published 27 Oct 2015

Selected synthetic strategies to cyclophanes

  • Sambasivarao Kotha,
  • Mukesh E. Shirbhate and
  • Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

Graphical Abstract
  • cyclophanes. To keep the length of the review at a manageable level the literature related to orthocyclophanes was not included. Keywords: addition reactions; coupling reactions; cyclophane; metathesis; muscopyridine; name reactions; natural products; Indroduction Cyclophanes [1][2][3][4][5][6][7][8][9][10
  • compounds which are discussed in detail in this review. Review Synthetic routes to cyclophanes Addition reactions Mannich reaction: In 2001, Erker and co-workers [84] have reported the synthesis of amino-substituted [3]ferrocenophane through an intramolecular Mannich reaction starting with the ferrocene
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Published 29 Jul 2015

Intermolecular addition reactions of N-alkyl-N-chlorosulfonamides to unsaturated compounds

  • Gerold Heuger and
  • Richard Göttlich

Beilstein J. Org. Chem. 2015, 11, 1226–1234, doi:10.3762/bjoc.11.136

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  • alkenes under copper(I) catalysis. In reactions of styrene derivatives with terminal double bonds the addition products were obtained in excellent yield and high regioselectivity. Lower yields are obtained in addition reactions to non-aromatic alkenes. The reaction most likely proceeds via a redox
  • catalysis and amidyl radicals, a concerted mechanism has been ruled out and a polar mechanism via chloronium ions would lead to the opposite regiochemistry. Keywords: addition reactions; catalysis; N-chlorosulfonamides; haloamination; radical reaction; Introduction In earlier publications we described the
  • as such electrophilic intermediates for an efficient intermolecular addition reaction. Addition reactions with N-alkyl-N-halosulfonamides to unsaturated compounds have not been examined in detail so far. In earlier works Komori added a secondary N-chloro-sulfonamide to 1-hexene under photoirridation
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Published 21 Jul 2015

Photocatalytic nucleophilic addition of alcohols to styrenes in Markovnikov and anti-Markovnikov orientation

  • Martin Weiser,
  • Sergej Hermann,
  • Alexander Penner and
  • Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2015, 11, 568–575, doi:10.3762/bjoc.11.62

Graphical Abstract
  • needed a suitable electron shuttle as additive. Comparison of MeOH addition reactions to substrate 1 in the presence of 0.4 and 1.0 equivalents of Ph–SH as additive showed differences in conversion rates, especially during the first six hours of irradiation (Figure 1). With stoichiometric amounts of Ph
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Published 27 Apr 2015

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

Graphical Abstract
  • demonstrated in the synthesis of many natural products, materials, and pharmacological agents. In the last three decades, there has been a significant increase in the development of asymmetric variants of this reaction. Unfortunately, conjugate addition reactions using α,β-unsaturated amides and lactams remain
  • underdeveloped due to their inherently low reactivity. This review highlights the work that has been done on both diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams. Keywords: α,β-unsaturated amides; α,β-unsaturated lactams; conjugate addition
  • addition reactions where they employed organocopper reagents and chiral phosphorus-based ligands [18]. This breakthrough in the field led to the development of different chiral ligands for asymmetric CA reactions. Another major advancement occurred in 1997 when Feringa’s group developed the first catalytic
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Published 23 Apr 2015

2-(1-Hydroxypropyn-2-yl)-1-vinylpyrroles: the first successful Favorsky ethynylation of pyrrolecarbaldehydes

  • A. V. Ivanov,
  • V. S. Shcherbakova,
  • I. A. Ushakov,
  • L. N. Sobenina,
  • O. V. Petrova,
  • A. I. Mikhaleva and
  • B. A. Trofimov

Beilstein J. Org. Chem. 2015, 11, 228–232, doi:10.3762/bjoc.11.25

Graphical Abstract
  • reactive N-vinyl group capable of various addition reactions [25][26][27][28][29][30] and polymerization [31][32][33], that remarkably extends their potential applications. Conclusion In conclusion, the base-mediated Favorsky direct ethynylation of pyrrolecarbaldehydes with free acetylene has been
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Published 10 Feb 2015

Selenium halide-induced bridge formation in [2.2]paracyclophanes

  • Laura G. Sarbu,
  • Henning Hopf,
  • Peter G. Jones and
  • Lucian M. Birsa

Beilstein J. Org. Chem. 2014, 10, 2550–2555, doi:10.3762/bjoc.10.266

Graphical Abstract
  • investigations on the intramolecular interaction of chemically disturbed functional groups in pseudo-geminally substituted [2.2]paracyclophanes, we report here the results of the addition reactions of selenium halides to pseudo-geminal bis(acetylenes). Results and Discussion Following our interest in the
  • bis(acetylene) 1. Reactions of selenium dichloride and selenium dibromide with 4,13-bis(propyn-1-yl)[2.2]paracyclophane (12). Addition reactions to bis(acetylene) 1. Addition reactions to 4,13-bis(propyn-1-yl)[2.2]paracyclophane 12. Supporting Information Supporting Information File 640: Detailed
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Published 31 Oct 2014

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

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Published 04 Sep 2014

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

  • Thilo Focken and
  • Stephen Hanessian

Beilstein J. Org. Chem. 2014, 10, 1848–1877, doi:10.3762/bjoc.10.195

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  • employed in organic synthesis primarily as stabilized anionic nucleophiles in addition reactions to electrophilic substrates with good to excellent stereocontrol. The products obtained from these reactions were used as key building blocks in the total synthesis of a variety of structurally highly diverse
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Published 13 Aug 2014

One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular SN2 reaction

  • Yiwen Xiong,
  • Ping Qian,
  • Chenhui Cao,
  • Haibo Mei,
  • Jianlin Han,
  • Guigen Li and
  • Yi Pan

Beilstein J. Org. Chem. 2014, 10, 1802–1807, doi:10.3762/bjoc.10.189

Graphical Abstract
  • corresponding β,γ-amino alcohols and vicinal diamines. α,β-Diamino acid derivatives have been served as organocatalysts, chiral ligands, chiral auxiliaries for asymmertric synthesis [10][11][12], as well as synthetic fragments for peptides and natural products [13]. Mannich-type addition reactions of α-amino
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Published 07 Aug 2014

Asymmetric Ugi 3CR on isatin-derived ketimine: synthesis of chiral 3,3-disubstituted 3-aminooxindole derivatives

  • Giordano Lesma,
  • Fiorella Meneghetti,
  • Alessandro Sacchetti,
  • Mattia Stucchi and
  • Alessandra Silvani

Beilstein J. Org. Chem. 2014, 10, 1383–1389, doi:10.3762/bjoc.10.141

Graphical Abstract
  • ethylamine residue. This outcome corroborated our previous achievements on addition reactions to ketimine 1. Figure 3 shows a working model able to explain the observed diastereoselectivity (R1 = t-Bu, R2 = CF3). The stereochemical outcome can be justified by the presence of the 1,3-allylic strain, which
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Published 18 Jun 2014

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C36H12 open geodesic polyarene

  • Hee Yeon Cho,
  • Ronald B. M. Ansems and
  • Lawrence T. Scott

Beilstein J. Org. Chem. 2014, 10, 956–968, doi:10.3762/bjoc.10.94

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  • unit. Representative synthetic reactions of fullerene C60 (2) include cyclopropanation [29][30], [3 + 2] cycloaddition [31][32], [4 + 2] cycloaddition [33], nucleophilic addition [34], and radical addition reactions [35]. Two of the earliest and most widely used reactions, the Bingel–Hirsch reaction
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Published 28 Apr 2014

Primary-tertiary diamine-catalyzed Michael addition of ketones to isatylidenemalononitrile derivatives

  • Akshay Kumar and
  • Swapandeep Singh Chimni

Beilstein J. Org. Chem. 2014, 10, 929–935, doi:10.3762/bjoc.10.91

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  • in Michael addition reactions via an iminium–enamine catalysis [31][32][33][34][35][36][37]. A few applications of primary-tertiary diamine in aldol reactions have been published [39][40][41][42][43]. To the best of our knowledge, however, the catalytic potential of amino acids derived primary
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Published 24 Apr 2014

Visible-light-induced, Ir-catalyzed reactions of N-methyl-N-((trimethylsilyl)methyl)aniline with cyclic α,β-unsaturated carbonyl compounds

  • Dominik Lenhart and
  • Thorsten Bach

Beilstein J. Org. Chem. 2014, 10, 890–896, doi:10.3762/bjoc.10.86

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  • -induced, iridium-catalyzed addition reactions to cyclic α,β-unsaturated carbonyl compounds. Typical reaction conditions included the use of one equivalent of the reaction substrate, 1.5 equivalents of the aniline and 2.5 mol % (in MeOH) or 1.0 mol % (in CH2Cl2) [Ir(ppy)2(dtbbpy)]BF4 as the catalyst. Two
  • suitable electrophilic leaving group for this purpose and addition reactions of α-aminoalkyl radicals to double bonds can be induced by irradiation of α-silylated amines in the presence of sensitizers such as 1,4-dicyanonaphthalene or 1,9-dicyanoanthracene. Addition reactions of this type have been broadly
  • used for the formation of carbon–carbon bonds [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. In non-silylated tertiary amines, a proton can act as a leaving group and photoinduced addition reactions of tertiary amines to enones are long known [23][24][25][26][27][28]. Mechanistically
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Published 17 Apr 2014

Direct and indirect single electron transfer (SET)-photochemical approaches for the preparation of novel phthalimide and naphthalimide-based lariat-type crown ethers

  • Dae Won Cho,
  • Patrick S. Mariano and
  • Ung Chan Yoon

Beilstein J. Org. Chem. 2014, 10, 514–527, doi:10.3762/bjoc.10.47

Graphical Abstract
  • electrophiles, allylsilanes and enolsilanes undergo addition reactions in which the α-trialkylsilyl groups are readily transfered even to weak silophiles. Over the past two decades, a variety of photochemical and electrochemical investigations have uncovered another interesting reactivity profile of
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Published 27 Feb 2014

Synthesis and stereochemical assignments of diastereomeric Ni(II) complexes of glycine Schiff base with (R)-2-(N-{2-[N-alkyl-N-(1-phenylethyl)amino]acetyl}amino)benzophenone; a case of configurationally stable stereogenic nitrogen

  • Hiroki Moriwaki,
  • Daniel Resch,
  • Hengguang Li,
  • Iwao Ojima,
  • Ryosuke Takeda,
  • José Luis Aceña and
  • Vadim A. Soloshonok

Beilstein J. Org. Chem. 2014, 10, 442–448, doi:10.3762/bjoc.10.41

Graphical Abstract
  • application [44][45][46][47]. In particular, homologation of Ni(II) complex 1 via alkyl halide alkylation [48][49][50], aldol [51][52][53], Mannich [54][55] and Michael [56][57][58] addition reactions can be conducted at room temperature and without specially controlled conditions. Achiral derivatives of 1
  • , compounds 2 [59][60] and 3 [61][62][63], show even greater features of practicality and found application in the convenient synthesis of symmetrically α,α-disubstituted α-AAs [64][65], homologation under asymmetric PTC [66][67] and Michael addition reactions [68][69][70][71][72]. Nevertheless, the
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Published 19 Feb 2014

Silica: An efficient catalyst for one-pot regioselective synthesis of dithioethers

  • Samir Kundu,
  • Babli Roy and
  • Basudeb Basu

Beilstein J. Org. Chem. 2014, 10, 26–33, doi:10.3762/bjoc.10.5

Graphical Abstract
  • under conditions A or moist with water (0.1 mL water for 0.5 g of silica) for use under conditions B. It was observed that allyl bromide or allyl iodide underwent sequential substitution–addition reactions entirely regioselectively with comparable yields (Table 1, entries 1–5), whereas allyl chloride
  • at room temperature. After the reaction, the product was purified by column chromatography (82% yield) and characterized as 1-(3-(phenylthio)propylthio)benzene (1,3-dithioether). Sequential substitution-addition reactions of thiols with allyl halides leading to the formation of 1,2 or 1,3
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Published 07 Jan 2014
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