Search for dissertations about: "Lewis acid"

Showing result 1 - 5 of 60 swedish dissertations containing the words Lewis acid.

  1. 1. Lewis Acid Mediated [2,3]-Sigmatropic Rearrangement of Allylic Ammonium Ylides

    University dissertation from Stockholm : Kemi

    Author : Jan Blid; KTH.; [2003]
    Keywords : Sigmatropic rearrangement; Lewis acid; Ammonium ylide; NMR spectroscopy; Density functional calculations;

    Abstract : This thesis describes a Lewis acid mediated[2,3]-sigmatropic rearrangement of various allylic ammoniumylides. Several Lewis acids are investigated and BBr3 and BF3are established to be the Lewis acids providing the highestconversion of the starting allylic amines. READ MORE

  2. 2. Development of New Methodology in Organic Synthesis: Lewis Acid-Mediated Rearrangements of Ammonium Ylides and Addition of 1, 3-bis(silyl) propenes to Aldehydes

    University dissertation from Stockholm : KTH

    Author : Pavel Tuzina; KTH.; [2009]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; asymmetric; amino acid; ammonium ylide; Lewis acid; microwave irradiation; NATURAL SCIENCES Chemistry Organic chemistry Organic synthesis; NATURVETENSKAP Kemi Organisk kemi Organisk syntes;

    Abstract : This thesis deals with the development of new methodologies in organicsynthesis. The main focus is on the development of Lewis acid-mediated [1,2]-rearrangements of ammonium ylides and the novel addition of 1,3-bis(silyl)propenes to carbonyl compounds. READ MORE

  3. 3. Lewis acid Mediated Aza-Diels-Alder Reactions and Asymmetric Alkylations of 2H-azirines

    University dissertation from Stockholm : Kemi

    Author : Erik Risberg; KTH.; [2004]
    Keywords : Enantioselective; diastereoselective; vinyl azide; 2H-azirines; aziridines; Lewis acid; chiral ligand; chiral auxiliary organolithiums Diels-Alder reaction alkyl radicals triethylborane.;

    Abstract : This thesis describes the use of 2H-azirines, three-membered unsaturatednitrogen-containing heterocycles, as reactive intermediates ina number of Lewis acid promoted alkylations and Diels-Alderreactions providing synthetically useful aziridines.In order to carry out this investigation a new generalprocedure for the ring closure of vinyl azides, forming theresultant 3-substituted-2H-azirines, was developed applying low boiling solventsin closed reaction vessels at elevated temperatures. READ MORE

  4. 4. Lewis Acid Mediated Alkylation and Diels-Alder Reactions of 2H-Azirines

    University dissertation from Stockholm : Kemi

    Author : Erik Risberg; KTH.; [2002]
    Keywords : 2H-azirines; Lewis acid activation; chiral ligandsorganolithium reagentsDiels-Alder reactions; DFT-calculations;

    Abstract : This thesis describes the use of 2H-azirines as reactivesubstrates in Lewis acid catalysed nucleophilic additions andin the Diels-Alder reaction.A number of carbon nucleophiles have been added to aseries of 2H-azirines in the presence and absence ofBF3·Et2O. READ MORE

  5. 5. Efficient Synthesis and Analysis of Chiral Cyanohydrins

    University dissertation from Stockholm : KTH

    Author : Stina Lundgren; KTH.; [2007]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; cyanohydrins; microreactor; polymersupported catalyst; ketonitriles; titanium; lanthanide; Lewis acid; Lewis base; NATURAL SCIENCES Chemistry Organic chemistry; NATURVETENSKAP Kemi Organisk kemi;

    Abstract : This thesis deals with the development of new methods for efficient synthesis and analysis in asymmetric catalysis. It focuses on the preparation of chiral cyanohydrins by enantioselective addition of cyanide to prochiral aldehydes. READ MORE