Change search
Refine search result
1 - 40 of 40
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Ahmad, Anees
    et al.
    Scarassati, Paulo
    Jalalian, Nazli
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Universidade de São Paulo, Brazil.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Silva, Luiz F., Jr.
    Oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III)2013In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 54, no 43, p. 5818-5820Article in journal (Refereed)
    Abstract [en]

    A novel protocol for the oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III) was developed. This approach uses inexpensive, readily available, and stable chemicals (PhI, mCPBA, and TsOH) giving rearrangement products in yields comparable to those obtained using the more expensive commercially available [hydroxy(tosyloxy)iodo]benzene [HTIB or Koser's reagent]. Additionally, an alternative protocol for the synthesis of 1-methyl-2-tetralone through the one-step epoxidation/rearrangement of 4-methyl-1,2-dihydronaphthalene using mCPBA and TsOH was developed.

  • 2.
    Bielawski, Marcin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Malmgren, Joel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pardo, Leticia M.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Wikmark, Ylva
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-Pot Synthesis and Applications of N-Heteroaryl Iodonium Salts2014In: ChemistryOpen, ISSN 2191-1363, Vol. 3, no 1, p. 19-22Article in journal (Refereed)
    Abstract [en]

    An efficient one-pot synthesis of N-heteroaryl iodonium triflates from the corresponding N-heteroaryl iodide and arene has been developed. The reaction conditions resemble our previous one-pot syntheses, with suitable modifications to allow N-heteroaryl groups. The reaction time is only 30min, and no anion exchange is required. The obtained iodonium salts were isolated in a protonated form, these salts can either be employed directly in applications or be deprotonated prior to use. The aryl groups were chosen to induce chemoselective transfer of the heteroaryl moiety to various nucleophiles. The reactivity and chemoselectivity of these iodonium salts were demonstrated by selectively introducing a pyridyl moiety onto both oxygen and carbon nucleophiles in good yields.

  • 3.
    Bielawski, Marcin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient one-pot synthesis of bis(4-tert-butylphenyl)iodonium triflate2009In: Organic Syntheses, ISSN 0078-6209, Vol. 86, p. 308-314Article in journal (Refereed)
  • 4.
    Bielawski, Marcin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    High-Yielding One-Pot Synthesis of Diaryliodonium Triflates from Arenes and Iodine or Aryl Iodides2007In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, no 24, p. 2521-2523Article in journal (Refereed)
    Abstract [en]

    Unsymmetric and symmetric diaryliodonium triflates are synthesized from both electron-deficient and electron-rich substrates in a fast, high yielding, and operationally simple protocol employing arenes and aryl iodides or iodine.

  • 5.
    Bielawski, Marcin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhu, Mingzhao
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient and general one-pot synthesis of diaryliodonium triflates: scope and limitations2007In: SIS Report: The 10th Symposium on Iodine Science, Chiba University, Japan 2007, 2007, p. 19-22Conference paper (Other academic)
  • 6. Brown, Michael
    et al.
    Delorme, Marion
    Malmedy, Florence
    Malmgren, Joel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Wirth, Thomas
    Synthesis of New Chiral Diaryliodonium Salts2015In: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, Vol. 26, no 11, p. 1573-1577Article in journal (Refereed)
    Abstract [en]

    A structurally diverse range of chiral diaryliodonium salts have been synthesised which have potential application in metal-free stereoselective arylation reactions.

  • 7.
    Dey, Chandan
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Lindstedt, Erik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Wallenberg Research Centre at Stellenbosch University, South Africa.
    Metal-Free C-Arylation of Nitro Compounds with Diaryliodonium Salts2015In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 17, no 18, p. 4554-4557Article in journal (Refereed)
    Abstract [en]

    An efficient, mild, and metal-free arylation of nitro-alkanes with diaryliodonium salts has been developed, giving easy access to tertiary nitro compounds. The reaction proceeds in high yields without the need for excess reagents and can be extended to alpha-arylation of nitroesters. Nitroalkanes were selectively C-arylated in the presence of other easily arylated functional groups, such as phenols and aliphatic alcohols.

  • 8.
    Ghosh, Raju
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Lindstedt, Erik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Jalalian, Nazli
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Room Temperature, Metal-Free Arylation of Aliphatic Alcohols2014In: ChemistryOpen, ISSN 2191-1363, Vol. 3, no 2, p. 54-57Article in journal (Refereed)
    Abstract [en]

    Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has been applied to the formal synthesis of butoxycaine.

  • 9.
    Ghosh, Raju
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Metal-Free Synthesis of N-Aryloxyimides and Aryloxyamines2014In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, no 6, p. 1830-1832Article in journal (Refereed)
    Abstract [en]

    N-Hydroxyphthalimide and N-hydroxysuccinimide have been arylated with diaryliodonium salts to provide N-aryloxyimides in excellent yields in short reaction times. A novel hydrolysis under mild and hydrazine-free conditions yielded aryloxyamines, which are valuable building blocks in the synthesis of oxime ethers and benzofurans.

  • 10.
    Jalalian, Nazli
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ishikawa, Eloisa E.
    Universidade de Sao Paulo, Instituto de Quimica.
    Silva Jr., Luiz F.
    Universidade de Sao Paulo, Instituto de Quimica.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Room temperature, metal-free synthesis of diaryl ethers with use of diaryliodonium salts2011In: Abstracts of Papers, 242nd ACS National Meeting & Exposition, Denver, CO, United States, August 28-September 1, 2011, American Chemical Society , 2011Conference paper (Other academic)
    Abstract [en]

    Diaryl ethers are common structural features in numerous natural products and biol. active compds.  Despite more than a century of immense focus on finding efficient synthetic routes to this compd. class, diaryl ethers remain difficult to obtain.  Routes that are catalytic in copper have been developed, but high catalyst loadings, excess reagents, elevated temps. and long reaction times are still needed.  Pd-catalyzed cross-couplings of phenols and aryl halides at temps. up to 100 °C have recently been reported to give high yields of diaryl ethers.  Diaryliodonium salts are non-toxic alternatives to transition metals in the synthesis of diaryl ethers and we have recently developed effective synthetic routes to these salts.  Herein we report a fast, high-yielding synthesis of diaryl ethers.  The reaction conditions are mild, metal-free, and avoid the use of halogenated solvents, additives, or excess reagents.  Precautions to avoid air or moisture are not needed.  The scope includes ortho- and halo-substituted diaryl ethers, which are difficult to obtain by metal-catalyzed protocols .

  • 11.
    Jalalian, Nazli
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Asymmetric α-arylation of carbonyl compounds with chiral diaryliodonium salts2009In: Abstracts of Papers, 238th ACS National Meeting, Washington, DC, United States, August 16-20, 2009, Washington, D.C.: American Chemical Society , 2009Conference paper (Other academic)
  • 12.
    Jalalian, Nazli
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Design and asymmetric synthesis of chiral diaryliodonium salts2010In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 66, no 31, p. 5793-5800Article in journal (Refereed)
    Abstract [en]

    The application of chiral hypervalent iodine reagents in asymmetric synthesis is highly desirable, as the reagents are metal-free, environmentally benign and employed under mild conditions. Three chiral diaryliodonium salts have been designed to provide chemoselectivity and asymmetric induction in asymmetric alpha-phenylation of carbonyl compounds. The synthetic routes to the selected targets are detailed herein, together with a structural investigation into the diastereoselectivity of the alkylation process.

  • 13.
    Jalalian, Nazli
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Synthesis of Koser’s Reagent and Derivatives2013In: Organic Syntheses, ISSN 0078-6209, Vol. 90, p. 1-9Article in journal (Refereed)
  • 14.
    Kervefors, Gabriella
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Becker, Antonia
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dey, Chandan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Metal-free formal synthesis of phenoxazine2018In: Beilstein Journal of Organic Chemistry, ISSN 2195-951X, E-ISSN 1860-5397, Vol. 14, p. 1491-1497Article in journal (Refereed)
    Abstract [en]

    A transition metal-free formal synthesis of phenoxazine is presented. The key step of the sequence is a high-yielding O-arylation of a phenol with an unsymmetrical diaryliodonium salt to provide an ortho-disubstituted diaryl ether. This species was cyclized to acetylphenoxazine in moderate yield. The overall yield in the three-step sequence is 72% based on recovered diaryl ether. An interesting, unusually stable iodine(III) intermediate in the O-arylation was observed by NMR and could be converted to the product upon longer reaction time.

  • 15. Küpper, Frithjof C.
    et al.
    Feiters, Martin C.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Kaiho, Tatsuo
    Yanagida, Shozo
    Zimmermann, Michael B.
    Carpenter, Lucy J.
    Luther, George W.
    Lu, Zunli
    Jonsson, Mats
    Kloo, Lars
    Purple fumes: the importance of iodine2013In: Science in School, ISSN 1818-0353, E-ISSN 1818-0361, no 27, p. 10p. 45-53Article in journal (Other academic)
  • 16.
    Lindberg, Bo G.
    et al.
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Merritt, Eleanor A.
    Rayl, Melanie
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Liu, Chenxiao
    Parmryd, Ingela
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Faye, Ingrid
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Immunogenic and Antioxidant Effects of a Pathogen-Associated Prenyl Pyrophosphate in Anopheles gambiae2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 8, p. e73868-Article in journal (Refereed)
    Abstract [en]

    Despite efficient vector transmission, Plasmodium parasites suffer great bottlenecks during their developmental stages within Anopheles mosquitoes. The outcome depends on a complex three-way interaction between host, parasite and gut bacteria. Although considerable progress has been made recently in deciphering Anopheles effector responses, little is currently known regarding the underlying microbial immune elicitors. An interesting candidate in this sense is the pathogen-derived prenyl pyrophosphate and designated phosphoantigen (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), found in Plasmodium and most eubacteria but not in higher eukaryotes. HMBPP is the most potent stimulant known of human V gamma 9V delta 2 T cells, a unique lymphocyte subset that expands during several infections including malaria. In this study, we show that V(Y)9V delta 2 T cells proliferate when stimulated with supernatants from intraerythrocytic stages of Plasmodium falciparum cultures, suggesting that biologically relevant doses of phosphoantigens are excreted by the parasite. Next, we used Anopheles gambiae to investigate the immune-and redox-stimulating effects of HMBPP. We demonstrate a potent activation in vitro of all but one of the signaling pathways earlier implicated in the human V(Y)9V delta 2 T cell response, as p38, JNK and PI3K/Akt but not ERK were activated in the A. gambiae 4a3B cell line. Additionally, both HMBPP and the downstream endogenous metabolite isopentenyl pyrophosphate displayed antioxidant effects by promoting cellular tolerance to hydrogen peroxide challenge. When provided in the mosquito blood meal, HMBPP induced temporal changes in the expression of several immune genes. In contrast to meso-diaminopimelic acid containing peptidoglycan, HMBPP induced expression of dual oxidase and nitric oxide synthase, two key determinants of Plasmodium infection. Furthermore, temporal fluctuations in midgut bacterial numbers were observed. The multifaceted effects observed in this study indicates that HMBPP is an important elicitor in common for both Plasmodium and gut bacteria in the mosquito.

  • 17.
    Lindstedt, Erik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ghosh, Raju
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Metal-Free Synthesis of Aryl Ethers in Water2013In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 15, no 23, p. 6070-6073Article in journal (Refereed)
    Abstract [en]

    The first arylation of allylic and benzylic alcohols with diaryliodonium salts is reported. The reaction yields alkyl aryl ethers under mild and metal-free conditions. Phenols are arylated to diaryl ethers in good to excellent yields. The reaction employs diaryliodonium salts and sodium hydroxide in water at low temperature, and excess amounts of the coupling partners are avoided.

  • 18.
    Lindstedt, Erik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Reitti, Marcus
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-Pot Synthesis of Unsymmetric Diaryliodonium Salts from Iodine and Arenes2017In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 82, no 22, p. 11909-11914Article in journal (Refereed)
    Abstract [en]

    The first synthesis of unsymmetric diaryliodonium salts directly from iodine and arenes is presented. The methodology provides diaryliodonium salts with the trimethoxyphenyl (TMP) moiety as dummy group. The protocol avoids the customary use of iodoarenes, which can be both expensive and toxic. Excess reagents are not required, and the reactions are performed under mild conditions. O-Arylations with these TMP salts were demonstrated to be highly chemoselective.

  • 19.
    Lindstedt, Erik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Stridfeldt, Elin
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Mild Synthesis of Sterically Congested Alkyl Aryl Ethers2016In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 18, no 17, p. 4234-4237Article in journal (Refereed)
    Abstract [en]

    An efficient and transition-metal-free method is presented to access tertiary alkyl aryl ethers by arylation of tertiary alcohols with ortho-substituted diaryliodonium salts. The scope covers cyclic and acyclic aliphatic, benzylic, allylic, and propargylic tertiary alcohols as well as primary and secondary fluorinated alcohols. The methodology gives access to alkyl aryl ethers of previously unprecedented steric congestion. Furthermore, the versatility of the developed procedure was demonstrated by arylation of the pro-drug mestranol.

  • 20.
    Lindström, Ulf M.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Somfai, Peter
    Microwave-assisted aminolysis of vinylepoxides1999In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 40, no 52, p. 9273-9276Article in journal (Refereed)
    Abstract [en]

    Di- and trisubstituted vinyl epoxides in NH4OH were subjected to microwave irradn. affording the corresponding vicinal amino alcs. in high yields. The reaction is stereospecific and highly regioselective for addn. at the allylic carbon. [on SciFinder(R)]

  • 21.
    Malmgren, Joel
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Nagendiran, Anuja
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Tai, Cheuk-Wai
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Bäckvall, Jan-Erling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    C-2 Selective Arylation of Indoles with Heterogeneous Nanopalladium and Diaryliodonium Salts2014In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 20, no 42, p. 13531-13535Article in journal (Refereed)
    Abstract [en]

    A simple and efficient method to prepare synthetically useful 2-arylindoles is presented, using a heterogeneous Pd catalyst and diaryliodonium salts in water under mild conditions. A remarkably low leaching of metal catalyst was observed under the applied conditions. The developed protocol is highly C-2 selective and tolerates structural variations both in the indole and in the diaryliodonium salt. Arylations of both NH indoles and N-protected indoles with ortho-substituted, electron-rich, electron-deficient, or halogenated diaryliodonium salts were achieved to give the desired products in high to excellent isolated yields within 6 to 15 h at room temperature or 40 °C.

  • 22.
    Malmgren, Joel
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Santoro, Stefano
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Jalalian, Nazli
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Himo, Fahmi
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Arylation with Unsymmetrical Diaryliodonium Salts: A Chemoselectivity Study2013In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, no 31, p. 10334-10342Article in journal (Refereed)
    Abstract [en]

    Phenols, anilines, and malonates have been arylated under metal-free conditions with twelve aryl(phenyl)iodonium salts in a systematic chemoselectivity study. A new “anti-ortho effect” has been identified in the arylation of malonates. Several “dummy groups” have been found that give complete chemoselectivity in the transfer of the phenyl moiety, irrespective of the nucleophile. An aryl exchange in the diaryliodonium salts has been observed under certain arylation conditions. DFT calculations have been performed to investigate the reaction mechanism and to elucidate the origins of the observed selectivities. These results are expected to facilitate the design of chiral diaryliodonium salts and the development of catalytic arylation reactions that are based on these sustainable and metal-free reagents.

  • 23.
    Merritt, Eleanor A.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Malmgren, Joel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Klinke, Felix J.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Synthesis of diaryliodonium triflates using environmentally benign oxidizing agents2009In: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, no 14, p. 2277-2280Article in journal (Refereed)
  • 24.
    Merritt, Eleanor A.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    α-Functionalization of carbonyl compounds using hypervalent iodine reagents2011In: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, no 4, p. 517-538Article in journal (Refereed)
    Abstract [en]

    α-Functionalized carbonyl compounds are versatile intermediates in organic synthesis. A broad range of both carbon and heteroatom substituents can be introduced into the α-position of carbonyl compounds using hypervalent iodine reagents. Herein we summarize the use of these environmentally benign reagents with particular emphasis on catalytic and asymmetric methodology developed over the past decade.

  • 25.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Fast, efficient and high-yielding routes to diaryliodonium salts2009In: European Symposium on Organic Chemistry (ESOC 16), Prague, Czech Republic, 2009, 2009Conference paper (Other academic)
  • 26.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Fast, efficient and high-yielding routes to diaryliodonium salts2009In: 44th EUCHEM Conference on Stereochemistry, Bürgenstock, Switzerland, May, 2009, 2009Conference paper (Other academic)
  • 27.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Fast, efficient and high-yielding routes to diaryliodonium salts2009In: XVIII EuCheMS Conference on Organometallic Chemistry, Gothenburg, Sweden, 2009, 2009Conference paper (Other academic)
  • 28.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Fast, efficient and high-yielding routes to diaryliodonium salts2009In: EUCHEMS Young Investigator Workshop, Liblice, Czech Republic, 2009, 2009Conference paper (Other academic)
  • 29.
    Olofsson, Berit
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Aggarwal, Varinder K.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective alfa-Arylation of Ketones: Application to the Synthesis of (–)-Epibatidine2006In: Sterochemistry, Bürgenstock, Switzerland, 2006Conference paper (Other (popular science, discussion, etc.))
  • 30.
    Olofsson, Berit
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Aggarwal, Varinder K.
    Bristol University, UK.
    Enantioselective alfa-Arylation of Ketones: Application to the Synthesis of (–)-Epibatidine2006In: Organikerdagarna, Kalmar, Sweden, 2006, p. Le21, P47-Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    The enantioselective introduction of electrophiles alfa to carbonyl compounds occupies a central position in asymmetric synthesis. Although asymmetric alkylations have been well developed, high enantioselectivity in α-arylation of ketones has only been achieved in a limited number of cases.

    We have developed a direct arylation reaction of cyclohexanones, employing diaryl iodonium(III) salts as electrophiles. The reaction was made enantioselective by the use of a chiral base, resulting in 2,4-substituted cyclohexanones in high yields and with high enantiomeric excesses and diastereoselectivities.

    This methodology was applied in a short, enantioselective synthesis of (–)-Epibatidine, an alkaloid recently isolated from the Ecuadorian poison frog Epipedobates tricolor. The synthesis was accomplished in 6 steps and 31% overall yield, thus providing the shortest and most efficient asymmetric route to this important compound to date.

  • 31.
    Olofsson, Berit
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Aggarwal, Varinder K.
    Bristol University, UK.
    Synthesis of Novel Heteroaryl Iodonium Salts and Enantioselective a-Arylation of Cyclohexanones2006In: 2nd Int. Conference on Hypervalent Iodine, 2006Conference paper (Other academic)
    Abstract [en]

    We have developed a direct arylation reaction of cyclohexanones employing diaryl iodonium(Ill) salts as electrophiles. The

    reaction was made enantiosilective by the use of a chiral base, resultinginZ,4-disubstituted cyclohexanones in high yields and with high enantiomeric excesses and diastereoselectivities. Novel heteroaryl iodonium salts were subsequently synthesized and employed in the coupling to variously substituted cyclohexanones.

  • 32.
    Reitti, Marcus
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Villo, Piret
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-Pot C-H Functionalization of Arenes by Diaryliodonium Salts2016In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 55, no 31, p. 8928-8932Article in journal (Refereed)
    Abstract [en]

    A transition-metal-free, mild, and highly regioselective synthesis of nitroarenes from arenes has been developed. The products are obtained in a sequential one-pot reaction by nitration of iodine(III) reagents with two carbon ligands, which are formed in situ from iodine(I). This novel concept has been extended to formation of aryl azides, and constitutes an important step towards catalytic reactions with these hypervalent iodine reagents. An efficient nitration of isolated diaryl-iodonium salts has also been developed, and the mechanism is proposed to proceed by a [2,2] ligand coupling pathway.

  • 33. Silva, Luiz F., Jr.
    et al.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Hypervalent iodine reagents in the total synthesis of natural products2011In: Natural product reports (Print), ISSN 0265-0568, E-ISSN 1460-4752, Vol. 28, no 10, p. 1722-1754Article, review/survey (Refereed)
    Abstract [en]

    This report describes the recent applications of hypervalent iodine reagents in the total synthesis of natural products. The large diversity of high-yielding and chemoselective reactions that can be achieved, even for highly functionalized molecules, is summarized, demonstrating that hypervalent iodine reagents have become an essential tool in synthetic organic chemistry.

  • 34. Siqueira, Fernanda A.
    et al.
    Ishikawa, Eloisa E.
    Fogaça, André
    Faccio, Andréa T.
    Carneiro, Vânia M. T.
    Soares, Rafael R. S.
    Utaka, Aline
    Tébéka, Iris R. M.
    Bielawski, Marcin
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Silva Jr., Luiz F.
    Metal-Free Synthesis of Indanes by Iodine(III)-Mediated Ring Contraction of 1,2-Dihydronaphthalenes2011In: Journal of the Brazilian Chemical Society, ISSN 0103-5053, E-ISSN 1678-4790, Vol. 22, no 9, p. 1795-1807Article in journal (Refereed)
    Abstract [en]

    A metal-free protocol was developed to synthesize indanes by ring contraction of 1,2-dihydronaphthalenes promoted by PhI(OH)OTs (HTIB or Koser’s reagent). This oxidative rearrangement can be performed in several solvents (MeOH, CH3CN, 2,2,2-trifluoroethanol (TFE), 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), and a 1:4 mixture of TFE:CH2Cl2) under mild conditions. The ring contraction diastereoselectively gives functionalized trans-1,3-disubstituted indanes, which are difficult to obtain in synthetic organic chemistry.

  • 35.
    Stridfeldt, Elin
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Lindstedt, Erik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Reitti, Marcus
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Blid, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Norrby, Per-Ola
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Competing Pathways in O-Arylations with Diaryliodonium Salts: Mechanistic Insights2017In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, no 53, p. 13249-13258Article in journal (Refereed)
    Abstract [en]

    A mechanistic study of arylations of aliphatic alcohols and hydroxide with diaryliodonium salts, to give alkyl aryl ethers and diaryl ethers, has been performed using experimental techniques and DFT calculations. Aryne intermediates have been trapped, and additives to avoid by-product formation originating from arynes have been found. An alcohol oxidation pathway was observed in parallel to arylation; this is suggested to proceed by an intramolecular mechanism. Product formation pathways via ligand coupling and arynes have been compared, and 4-coordinated transition states were found to be favored in reactions with alcohols. Furthermore, a novel, direct nucleophilic substitution pathway has been identified in reactions with electron-deficient diaryliodonium salts.

  • 36.
    Tinnis, Fredrik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Stridfeldt, Elin
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Lundberg, Helena
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Adolfsson, Hans
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Stellenbosch University, South Africa.
    Metal-Free N-Arylation of Secondary Amides at Room Temperature2015In: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 17, no 11, p. 2688-2691Article in journal (Refereed)
    Abstract [en]

    The arylation of secondary acyclic amides has been achieved with diaryliodonium salts under mild and metal-free conditions. The methodology has a wide scope, allows synthesis of tertiary amides with highly congested aryl moieties, and avoids the regioselectivity problems observed in reactions with (diacetoxyiodo)benzene.

  • 37.
    Tolnai, Gergely L.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Nilsson, Ulf J.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient O-Functionalization of Carbohydrates with Electrophilic Reagents2016In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 55, no 37, p. 11226-11230Article in journal (Refereed)
    Abstract [en]

    Novel methodology for O-functionalization of carbohydrate derivatives has been established using bench-stable and easily prepared iodonium(III) reagents. Both electron-withdrawing and electron-donating aryl groups were introduced under ambient conditions and without precautions to exclude air or moisture. Furthermore, the approach was extended both to full arylation of cyclodextrin, and to trifluoroethylation of carbohydrate derivatives. This is the first general approach to introduce traditionally non-electrophilic groups into any of the OH groups around the sugar backbone. The methodology will be useful both in synthetic organic chemistry and biochemistry, as important functional groups can be incorporated under simple and robust reaction conditions in a fast and efficient manner.

  • 38.
    Utas, Josefin E.
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Åkermark, Björn
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Efficient Synthesis of 2-Substituted Imidazoles by Palladium-Catalyzed Cross-Coupling with Benzylzinc Reagents2006In: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, no 12, p. 1965-1967Article in journal (Refereed)
    Abstract [en]

    Substituted benzylzinc reagents have been used in novel cross-coupling reactions with 2-iodo imidazoles to form compounds containing both a phenol and an imidazole moiety. The ­intramolecular hydrogen-bonding properties of these compounds were subsequently studied.

  • 39.
    Villo, Piret
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry. University of Tartu, Estonia.
    Kervefors, Gabriella
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Transition metal-free, chemoselective arylation of thioamides yielding aryl thioimidates or N-aryl thioamides2018In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, no 64, p. 8810-8813Article in journal (Refereed)
    Abstract [en]

    Reactions of secondary thioamides with diaryliodonium salts under basic, transition metal-free conditions resulted in chemoselective S-arylation to provide aryl thioimidates in good to excellent yields. Equimolar amounts of thioamide, base and diaryliodonium salt were sufficient to obtain a diverse selection of products within short reaction times. Reactions with thiolactams delivered N-arylated thioamides in good yield at room temperature.

  • 40.
    Zhu, Mingzhao
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Jalalian, Nazli
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Olofsson, Berit
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-pot synthesis of diaryliodonium salts using toluenesulfonic acid - a fast entry to electron-rich diaryliodonium tosylates and triflates2008In: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, no 4, p. 592-596Article in journal (Refereed)
    Abstract [en]

    A direct synthesis of symmetric and unsymmetric electron-rich diaryliodonium salts is described. The use of MCPBA and toluenesulfonic acid delivers diaryliodonium tosylates in high yields. An in situ anion exchange has also been developed, giving access to the corresponding triflate salts.

1 - 40 of 40
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf