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Showing result 1 - 5 of 25 swedish dissertations matching the above criteria.

  1. 1. Radical Cyclization Approaches to Pyrrolidines

    Author : Magnus Beşev; Troels Skrydstrup; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Radical cyclization; diastereselectivity; pyrrolidine; pyrroline; thiazoline; aziridine; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Abstract : Five-membered rings are readily prepared by 5-exo-trig radical cyclization. This thesis is concerned with novel methodology for pyrrolidine synthesis. We have synthesised selenium containing radical precursors from aziridines and α-phenylseleno ketones, and cyclized them to 2,4- and 3,4-disubstituted pyrrolidines. READ MORE

  2. 2. Synthesis of N-Containing Compounds: Development of Methodology and its Application in Total Synthesis

    Author : Lu Yu; Centrum för analys och syntes; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; a-keto amides; enamine catalysis; pyrrolidine; TEMPO; a-keto thioamides; a-keto amidines; a-amino-b-hydroxy ester; asymmetric transfer hydrogenation; alexine; dynamic kinetic resolution; hydroamination; 1; 2-diamines; enamines; copper;

    Abstract : This thesis aims to develop new synthetic methods and explore the possibilities to apply it in the total synthesis of natural products.Chapter 2 deals with a mild procedure for the synthesis of a-keto amides by a-oxidation of the corresponding aketo amines mediated by pyrrolidine and TEMPO. READ MORE

  3. 3. Construction of Five-Membered Heterocyclic Compounds via Radical Cyclization

    Author : Stefan Berlin; Lars Engman; Mario D. Bachi; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; radical; cyclization; carbonylation; melatonin; pyrrolidine; pyrrolidin-3-one; tetrahydrofuran-3-one; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Abstract : This thesis describes how radical cyclization chemistry can be applied for the construction of heterocyclic compounds.In the first part, a series of electron deficient α-phenylselenenylalkenes were prepared via a PhSeCl-addition/HCl-elimination sequence. READ MORE

  4. 4. Synthesis of Tetrahydrofuran and Pyrrolidine Derivatives Utilising Radical Reactions : Organochalcogenides in Reductive, Carbonylative and Group-Transfer Cyclisation

    Author : Cecilia Ericsson; Lars Engman; Ilhyong Ryu; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Organisk kemi; Organic chemistry; Organisk kemi;

    Abstract : This thesis describes free-radical reactions for the construction of tetrahydrofuran and pyrrolidine derivatives. The studies are concerned with (i) diastereoselectivity in radical cyclisation, (ii) construction of tetrahydrofuran-3-ones and pyrrolidin-3-ones via radical carbonylation/cyclisation and (iii) synthesis of tetrahydrofuran derivatives via group-transfer cyclisation of organochalcogen compounds. READ MORE

  5. 5. 1. Asymmetric aldol and alkylation reactions using pyrrolidine-based chiral auxiliaries 2. Syntheses of pine sawfly pheromone precursors and structurally related compounds

    Author : Fredrik Andersson; KTH; []
    Keywords : Chiral auxiliary; Stereoselectivity; Lewis acid; Aldol; Alkylation; Sex pheromone; Pine sawfly; Lipase; Synthesis; Diprion nipponica; Macrodiprion memoralis; Microdiprion pallipes; ;

    Abstract : This thesis describes the syntheses of the 1-propionylatedauxiliaries (S)-(− )-2-(pyrrolidin-2-yl)propan-2-ol and (S)-(− )-2-(1-methoxy-1-methylethyl)pyrrolidine andtheir use in asymmetric aldol and alkylation reactions. Thesynthesis of 1-propionylated (2S,4R) 2-{4-[(tert-butyldimethylsilyl)oxy]pyrrolidin-2-yl}propan-2-olis also described. READ MORE