Search for dissertations about: "alder"

Showing result 16 - 20 of 59 swedish dissertations containing the word alder.

  2. 16. Synthesis and Reactivity Studies of Zwitterionic Silenes and 2-Silenolates

    Author : Tamaz Guliashvili; Henrik Ottosson; Kim M. Baines; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Silicon; Zwitterionic Silene; 2-Silenolate; Diels-Alder Reaction; Silacyclohexene; X-ray Crystallography; Organisk kemi; Organic chemistry; Organisk kemi;

    Abstract : This thesis describes synthesis and reactivity studies of 2-amino-2-siloxysilenes and 2-silenolates, species that are strongly influenced by reversed Si=C bond polarization, i.e. an Siδ-=Cδ+ polarization as compared to the natural Siδ+=Cδ- polarization. READ MORE

  4. 17. Design, Synthesis and Evaluation of Photoswitches for Molecular Solar Thermal Energy Storage Systems

    Author : Maria Quant; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Solar fuels; Norbornadiene; Tetracyclooctane.; Quadricyclane; Energy storage and release; Solar energy; Photoswitches; Molecular solar thermal energy storage; Diels-Alder reaction; Bicyclooctadiene; Energy conversion;

    Abstract : To meet the future energy demands and handle climate changes, new sustainable energy sources must be developed. Over the last decades, great scientific progress on harvesting solar energy has been made, but storing the energy is still a challenge. READ MORE

  5. 18. Heart rot of spruce and alder in forests of Latvia : impact and possibilities for silvicultural control

    Author : Natalija Arhipova; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Abstract : Heart rot causes great decrease in timber quality throughout the world. In the conifer forests of Northern Hemisphere the most significant losses are caused by fungi from the Heterobasidion annosum species complex. READ MORE

  6. 19. Development and application of new chiral -amino alcohols in synthesis and catalysis : Use of 2-azanorboryl-3-methanols as common intermediates in synthesis and catalysis

    Author : Pedro Pinho; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Asymmetric synthesis; hetero-Diels-Alder reactions; chiral cyclopentyl-amines; chiral ligands and catalysts; amino alcohols; asymmetric reductions; ruthenium transfer hydrogenation; oxazaborolidines; asymmetric additions; dialkylzinc reagents; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Abstract : The development and application of unnatural amino alcohols,prepared via hetero-Diels-Alder reactions,in synthesis and catalysis is described.The studies are concerned with the [i]scope of the hetero-Diels-Alder reaction and preparation of important intermediates in the synthesis of antiviral agents,[ii ]application of amino alcohols in the ruthenium transfer hydrogenation of ketones,[iii ]use of similar precursors in the in situ generation of oxazaborolidines for reduction of ketones,and [iv] development and application of new chiral auxiliaries for dialkylzinc additions to activated imines, respectively. READ MORE

  7. 20. Synthesis and Rearrangement of Epoxy Sugars

    Author : Fritiof Pontén; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organisk kemi; Organic chemistry; crown ether; silica; Intramoleculaf Diels-Alder reaction; radical allylation; allyl sulfone; sugar epoxide; allyl sulfide; ring-contraction; C-glycoside; a; IMDAF; b-unsaturated aldehyde;

    Abstract : Ring-Contraction of sugar-derived epoxy alcohols, functionalised in position 1 and 6, by treatment with lithium bromide and N, N, N', N'-tetramethylurea in refluxing toluene gave enantiomerically pure a,b-unsaturated aldehydes of furanosides. O-Glycosidic epoxy alcohols gave only one, easily purified, aldehyde in approximately 30-60% yield depending on the substitution pattern. READ MORE