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  • 1.
    Cadu, Alban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Iridium Catalysed Asymmetric Hydrogenation of Pyridines2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis presents the hydrogenation of substituted pyridines using N,P-ligated iridium catalystsin homogeneous media. These iridium catalysts were developed within this research group in thepast decade. This method of hydrogenation is highly stereoselective, and in several cases good to excellent ees were obtained.The hydrogenation of substituted pyridines was studied: by screening for the catalyst giving thehighest conversion and ee, by optimising the reaction conditions and by attempting to improve existingcatalysts. New substrates were synthesised for this process, in particular alkyl substituted Nprotectedpyridines. Their reduction provided chiral piperidines, which could be used as chiralbuilding blocks once deprotected.

    Delarbeten
    1. Iridium-Catalyzed Asymmetric Hydrogenation of Substituted Pyridines
    Öppna denna publikation i ny flik eller fönster >>Iridium-Catalyzed Asymmetric Hydrogenation of Substituted Pyridines
    2013 (Engelska)Ingår i: Asian Journal of Organic Chemistry, ISSN 2193-5807, Vol. 2, nr 12, s. 1061-1065Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Asymmetric hydrogenation of ortho-substituted pyridines catalyzed by N,P-ligated iridium is demonstrated. To facilitate this reaction, the aromaticity of the pyridines was weakened by forming N-iminopyridium ylides. The reactions give very high conversions, and after a single recrystallization, excellent ee of up to 98 % was obtained. This method lends itself to the synthesis of chiral piperidine building blocks.

    Nyckelord
    hydrogenation, iridium, N-iminopyridium ylides, pyridines, selective catalysis
    Nationell ämneskategori
    Organisk kemi Oorganisk kemi
    Forskningsämne
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-212412 (URN)10.1002/ajoc.201300160 (DOI)000328218000008 ()
    Tillgänglig från: 2013-12-10 Skapad: 2013-12-10 Senast uppdaterad: 2017-01-25Bibliografiskt granskad
  • 2.
    Cadu, Alban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Noble Metal Catalysed Reductions and Rearrangements2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The focus of this thesis has been organometallic catalysis applied to compounds containing heteroatoms which are usually poisonous to metal catalysts, by channelling their innate reactivity advantageously. The studies described in this thesis concentrate, in the first part, on iridium catalysed asymmetric hydrogenation (papers I and II) and in the second part, on gold catalysed internal rearrangements (papers III and IV). In each case, two classes of compounds are studied: pyridinium salts or sulphurous compounds. The asymmetric hydrogenation of pyridinium compounds was performed with 2% loading of N,P-ligated Ir catalyst with I2 additive (paper I) to achieve moderate to good enantiomeric excess (up to 98%). In paper II, olefinic sulphones were hydrogenated with an efficient 0.5% catalytic loading. In most cases full conversion was obtained and with good to excellent ees (up to 99%). The products of these reductions are chiral compounds, which could constitute further chemical building blocks. Palladium and gold were used sequentially in paper III, in order to perform a “Click” thiol-yne reaction followed by a semi-Pinacol rearrangement, leading to isolated yields of up to 98%. In paper IV The gold catalysed rearrangement of alkyl-pyridinium diynes was conducted, with a number of substrates providing >90% NMR yield. A highly selective hydrogenation was performed with a heterogeneous palladium catalyst to yield single diastereomer products. This methodology consists of up to three steps, with two catalysts in one pot.

    Delarbeten
    1. Iridium-Catalyzed Asymmetric Hydrogenation of Substituted Pyridines
    Öppna denna publikation i ny flik eller fönster >>Iridium-Catalyzed Asymmetric Hydrogenation of Substituted Pyridines
    2013 (Engelska)Ingår i: Asian Journal of Organic Chemistry, ISSN 2193-5807, Vol. 2, nr 12, s. 1061-1065Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Asymmetric hydrogenation of ortho-substituted pyridines catalyzed by N,P-ligated iridium is demonstrated. To facilitate this reaction, the aromaticity of the pyridines was weakened by forming N-iminopyridium ylides. The reactions give very high conversions, and after a single recrystallization, excellent ee of up to 98 % was obtained. This method lends itself to the synthesis of chiral piperidine building blocks.

    Nyckelord
    hydrogenation, iridium, N-iminopyridium ylides, pyridines, selective catalysis
    Nationell ämneskategori
    Organisk kemi Oorganisk kemi
    Forskningsämne
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-212412 (URN)10.1002/ajoc.201300160 (DOI)000328218000008 ()
    Tillgänglig från: 2013-12-10 Skapad: 2013-12-10 Senast uppdaterad: 2017-01-25Bibliografiskt granskad
    2. An Enantioselective Approach to the Preparation of Chiral Sulfones by Ir-Catalyzed Asymmetric Hydrogenation
    Öppna denna publikation i ny flik eller fönster >>An Enantioselective Approach to the Preparation of Chiral Sulfones by Ir-Catalyzed Asymmetric Hydrogenation
    Visa övriga...
    2014 (Engelska)Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 136, nr 47, s. 16557-16562Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Several chiral sulfonyl compounds were prepared using the iridium catalyzed asymmetric hydrogenation reaction. Vinylic, allylic and homoallylic sulfone substitutions were investigated, and high enantioselectivity is maintained regardless of the location of the olefin with respect to the sulfone. Impressive stereoselectivity was obtained for dialkyl substitutions, which typically are challenging substrates in the hydrogenation. As expected, the more bulky Z-substrates were hydrogenated slower than the corresponding E isomers, and in slightly lower enantioselectivity.

    Ort, förlag, år, upplaga, sidor
    American Chemical Society (ACS), 2014
    Nationell ämneskategori
    Organisk kemi
    Forskningsämne
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-236862 (URN)10.1021/ja5079877 (DOI)000345720500016 ()25300238 (PubMedID)
    Tillgänglig från: 2014-11-24 Skapad: 2014-11-24 Senast uppdaterad: 2017-12-05Bibliografiskt granskad
    3. One-Pot Synthesis of Keto Thioethers by Palladium/Gold-Catalyzed Click and Pinacol Reactions
    Öppna denna publikation i ny flik eller fönster >>One-Pot Synthesis of Keto Thioethers by Palladium/Gold-Catalyzed Click and Pinacol Reactions
    Visa övriga...
    2014 (Engelska)Ingår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 21, s. 5556-5559Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    An atom-efficient synthesis of keto thioethers was devised via tandem gold/palladium catalysis. The reaction proceeds through a regioselective thiol attack at the β-position of the alcohol, followed by an alkyl, aryl, or benzyl 1,2-shift. Both acyclic and cyclic systems were studied, in the latter case leading to the ring expansion of cyclic substrates.

    Ort, förlag, år, upplaga, sidor
    American Chemical Society (ACS), 2014
    Nyckelord
    Gold, Palladium, thioether, catalysis, synthesis
    Nationell ämneskategori
    Organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-236857 (URN)10.1021/ol502553p (DOI)000344635200013 ()25325145 (PubMedID)
    Tillgänglig från: 2014-11-24 Skapad: 2014-11-24 Senast uppdaterad: 2017-12-05Bibliografiskt granskad
    4. Dual Gold (I) Catalysed Cyclisation of Dialkynyl Pyridinium salts
    Öppna denna publikation i ny flik eller fönster >>Dual Gold (I) Catalysed Cyclisation of Dialkynyl Pyridinium salts
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Novel dialkynyl pyridines were synthesised and protected as alkyl salts for dual gold (I) catalysed cycloisomerisation. Different alkyl groups and counter ions were screened for the salts, with benzyl and PF6- providing the best results. The cyclisation led to NMR yields of >95% being obtained for a number of substrates. Step-wise hydrogenation of products could be carried out in one-pot by Pd/C, with selective reduction of the double bonds, followed by deprotection of the Bn group.

    Nyckelord
    chemistry
    Nationell ämneskategori
    Organisk kemi
    Forskningsämne
    Kemi med inriktning mot organisk kemi
    Identifikatorer
    urn:nbn:se:uu:diva-272369 (URN)
    Tillgänglig från: 2016-01-13 Skapad: 2016-01-13 Senast uppdaterad: 2016-02-12Bibliografiskt granskad
  • 3.
    Cadu, Alban
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Andersson, Pher G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Development of iridium-catalyzed asymmetric hydrogenation: New catalysts, new substrate scope2012Ingår i: Journal of Organometallic Chemistry, ISSN 0022-328X, E-ISSN 1872-8561, Vol. 714, s. 3-11Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    A review. The asym. hydrogenation of olefins is a tremendously powerful tool used to synthesize chiral mols. The field was pioneered using rhodium- and ruthenium- based catalysts; however, catalysts based on both of these metals suffer from limitations, such as the need for directing substituents near or even adjacent to the olefin. Iridium-based catalysts do not suffer from this flaw and can thus hydrogenate a wide variety of olefins, including some tetra substituted ones. It is also possible for iridium-based catalysts to hydrogenate hetero-π bonds such as those found in heteroarom. rings. This review summarizes the contributions made to this field by the authors in the past few years. [on SciFinder(R)]

  • 4.
    Cadu, Alban
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Andersson, Pher G
    Iridium catalysis: Application of asymmetric reductive hydrogenation2013Ingår i: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 42, nr 40, s. 14345-14356Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iridium, despite being one of the least abundant transition metals, has found several uses. N,P-ligated iridium catalysts are used to perform many highly selective reactions. These methodologies have been developed extensively over the past 15 years. More recently, the application of iridium N,P catalysts in asymmetric hydrogenation has been a focus of research to find novel applications and to expand on their current synthetic utility. The aim of this perspective is to highlight the advances made by the Andersson group.

  • 5.
    Cadu, Alban
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Paptchikhine, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Andersson, Pher G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för biokemi och organisk kemi.
    Birch Reaction Followed by Asymmetric Iridium-Catalysed Hydrogenation2011Ingår i: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, nr 23, s. 3796-3800Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Birch reaction products are asymmetrically hydrogenated with high enantio- and diastereoselectivity via iridium catalysts. This new method of producing chiral compounds was explored for a variety of 1,3-di- and 1,2,4-tri-substituted cyclohexadienes.

  • 6.
    Cadu, Alban
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Upadhyay, Puspesh K.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Andersson, Pher G.
    Stockholm University.
    Iridium-Catalyzed Asymmetric Hydrogenation of Substituted Pyridines2013Ingår i: Asian Journal of Organic Chemistry, ISSN 2193-5807, Vol. 2, nr 12, s. 1061-1065Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Asymmetric hydrogenation of ortho-substituted pyridines catalyzed by N,P-ligated iridium is demonstrated. To facilitate this reaction, the aromaticity of the pyridines was weakened by forming N-iminopyridium ylides. The reactions give very high conversions, and after a single recrystallization, excellent ee of up to 98 % was obtained. This method lends itself to the synthesis of chiral piperidine building blocks.

  • 7.
    Cadu, Alban
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Watile, Rahul
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    Biswas, Srijit
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC.
    Orthaber, Andreas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström.
    Sjöberg, Per J
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Analytisk kemi.
    Samec, Joseph
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    One-Pot Synthesis of Keto Thioethers by Palladium/Gold-Catalyzed Click and Pinacol Reactions2014Ingår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 21, s. 5556-5559Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An atom-efficient synthesis of keto thioethers was devised via tandem gold/palladium catalysis. The reaction proceeds through a regioselective thiol attack at the β-position of the alcohol, followed by an alkyl, aryl, or benzyl 1,2-shift. Both acyclic and cyclic systems were studied, in the latter case leading to the ring expansion of cyclic substrates.

  • 8. Peters, Byron K.
    et al.
    Zhou, Taigang
    Rujirawanich, Janjira
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Cadu, Alban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Singh, Thishana
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Rabten, Wangchuk
    Kerdphon, Suttichat
    Andersson, Pher G.
    An Enantioselective Approach to the Preparation of Chiral Sulfones by Ir-Catalyzed Asymmetric Hydrogenation2014Ingår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 136, nr 47, s. 16557-16562Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Several chiral sulfonyl compounds were prepared using the iridium catalyzed asymmetric hydrogenation reaction. Vinylic, allylic and homoallylic sulfone substitutions were investigated, and high enantioselectivity is maintained regardless of the location of the olefin with respect to the sulfone. Impressive stereoselectivity was obtained for dialkyl substitutions, which typically are challenging substrates in the hydrogenation. As expected, the more bulky Z-substrates were hydrogenated slower than the corresponding E isomers, and in slightly lower enantioselectivity.

  • 9.
    Tsupova, Svetlana
    et al.
    Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany..
    Cadu, Alban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Organisk kemi. Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany..
    Stuck, Fabian
    Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany..
    Rominger, Frank
    Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany..
    Rudolph, Matthias
    Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany..
    Samec, Joseph S. M.
    Stockholm Univ, Dept Organ Chem, S-10691 Stockholm, Sweden..
    Hashmi, A. Stephen K.
    Heidelberg Univ, Organ Chem Inst, Neuenheimer Feld 270, D-69120 Heidelberg, Germany.;King Abdulaziz Univ, Fac Sci, Dept Chem, Jeddah 21589, Saudi Arabia..
    Dual Gold(I)-catalyzed Cyclization of Dialkynyl Pyridinium Salts2017Ingår i: ChemCatChem, ISSN 1867-3880, E-ISSN 1867-3899, Vol. 9, nr 11, s. 1915-1920Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Novel dialkynyl pyridines were synthesized and protected as alkyl salts for dual gold(I)-catalyzed cycloisomerization. Different alkyl groups and counter ions were screened for the salts, with benzyl and hexafluorophosphate providing the best results. The cyclization led to NMR yields of >95% being obtained for a number of substrates. Step-wise hydrogenation of products could be performed in one-pot by Pd/C, with selective reduction of the double bonds, followed by deprotection of the benzyl group.

  • 10.
    Tšupova, Svetlana
    et al.
    Ruprecht-Karls-Universität Heidelberg.
    Cadu, Alban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi.
    Stuck, Fabian
    Ruprecht-Karls-Universität Heidelberg.
    Rominger, Frank
    Ruprecht-Karls-Universität Heidelberg.
    Rudolph, Matthias
    Ruprecht-Karls-Universität Heidelberg.
    Samec, Joseph
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - BMC, Syntetisk organisk kemi. Stockholm University.
    Hashmi, A. Stephen K.
    Ruprecht-Karls-Universität Heidelberg.
    Dual Gold (I) Catalysed Cyclisation of Dialkynyl Pyridinium saltsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Novel dialkynyl pyridines were synthesised and protected as alkyl salts for dual gold (I) catalysed cycloisomerisation. Different alkyl groups and counter ions were screened for the salts, with benzyl and PF6- providing the best results. The cyclisation led to NMR yields of >95% being obtained for a number of substrates. Step-wise hydrogenation of products could be carried out in one-pot by Pd/C, with selective reduction of the double bonds, followed by deprotection of the Bn group.

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