Sökning: "Diels-Alder Reaction"

Visar resultat 1 - 5 av 27 avhandlingar innehållade orden Diels-Alder Reaction.

1. 1. Computational Studies and Design of Biomolecular Diels-Alder Catalysis

   Författare :Mats Linder; Tore Brinck; Kendall N. Houk; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computational chemistry; density functional theory; enzyme design; molecular modeling; organocatalysis; stepwise Diels-Alder; oxyanion hole;

   Sammanfattning : The Diels-Alder reaction is one of the most powerful synthetic tools in organic chemistry, and asymmetric Diels-Alder catalysis allows for rapid construction of chiral carbon scaffolds. For this reason, considerable effort has been invested in developing efficient and stereoselective organo- and biocatalysts. LÄS MER

3. 2. On the Ring-Opening Reaction of Thiophene-1,1-dioxides and the Intramolecular Diels-Alder Reaction of Azanona- and AzadecatrienesI

   Författare :Anders Sebastian Tsirk; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; transition states; 3-21G * ; intramolecular Diels-Alder reactions; asymmetric induction; multivariate optimization; kinetic isotope effects; rearrangements; secondary amines; 1-dioxides; Ring-opening reaction; thiophene-1; stereoselectivity.; Organic chemistry; Organisk kemi;

   Sammanfattning : Substituted thiophene-1,1-dioxides were synthesized and their ring-opening reactions with omega-unsaturated secondary amines were investigated; this led to a synthetic route to azatrienes and to the preparation of some polyhydroisoindoles and polyhydroisoquinolines via an intramolecular Diels-Alder reaction. By using 2-substituted pyrrolidines and piperidines various tetrahydrobenzo[f]indolizidines, benzo[b]quinolizidines, tetrahydrobenzo[a]indolizidines and tetrahydro[a]pyrrolizidines could be synthesized via the ring-opening of 3-bromo-2,5-dimmethylthiophene-1,1-dioxide and a subsequent intramolecular Diels-Alder reaction. LÄS MER

4. 3. Developments in the Field of Aza-Diels-Alder Reactions, Catalytic Michael Additions and Automated Synthesis

   Författare :Stefan Modin; Pher Andersson; Lars Engman; Hans Adolfsson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Asymmetric synthesis; aza-Diels-Alder; Michael addition; Transfer hydrogenation; automated synthesis; Catalysis; Organisk kemi; Organic chemistry; Organisk kemi;

   Sammanfattning : The development of new aza-bicyclic structures with potential applications as ligands synthesised via an aza-Diels-Alder cycloaddition has been studied. The studies are concerning the i) development of large scale aza-Diels-Alder reaction, ii) development of a fast and simple route to bicyclic diamine ligands, iii) development of new aza-Diels-Alder adducts from different dienes, iv) development and application of bicyclic N,P ligands for catalytic Michael additions and v) development of robotized asymmetric transfer hydrogenation reactions. LÄS MER

5. 4. Natural Product Synthesis and Development of Novel Reaction Methodology

   Författare :Jakob Danielsson; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; perophoramidine; communesin; quaternary stereocenter; Diels-Alder; 1; 2-asymmetric induction; polar Felkin-Anh; Cornforth-Evans; Mukaiyama aldol; 3-dipolar cycloaddition; azomethine ylide; 2-amino alcohol; anti-α-amino-β-hydroxy ester;

   Sammanfattning : This thesis deals with the development of new reaction methodology for stereoselective synthesis, as well as total synthesis of natural products and investigations of the stereochemical outcome in the Mukaiyama aldol reaction. Chapter 2 describes efforts made towards the total synthesis of the oxindole natural products perophoramidine and the communesin. LÄS MER

7. 5. Towards Rational Design of Asymmetric Catalyst for Organometallic and Organocatalytic Reactions

   Författare :Antti Hartikka; Per Arvidsson; Albrecht Berkessel; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organocatalysis; Transition Metal Complex; Asymmetric; Aldol Reaction; Cyclopropanation; Diels-Alder; Reduction; Conjugate Addition; Organic chemistry; Organisk kemi;

   Sammanfattning : This thesis deals with synthetically modified chiral molecules and their application in asymmetric catalysis. The first part of the thesis describes the use of commercially available chiral diamine ligands in the iridium catalyzed transfer hydrogenation of aromatic ketones. LÄS MER