Search for dissertations about: "ring opening reaction"

Showing result 1 - 5 of 60 swedish dissertations containing the words ring opening reaction.

2. 1. Development of ring-opening catalysts for diesel quality improvement

   Author : Ulf Nylén; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ring opening; naphthenes; cetane number improvement; indan; light cycle oil LCO ; Pt-Ir catalyst; catalyst characterization; aromatic sulphur compounds; GC-SCD; distribution; analysis;

   Abstract : The global oil refining industry with its present shift inproduct distribution towards fuels such as gasoline and dieselwill most likely hold the fort for many years to come. However,times will change and survival will very much depend onprocessing flexibility and being at the frontiers of refiningtechnology, a technology where catalysts play leading roles. READ MORE

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

   Author : Anders Sebastian Tsirk; Centrum för analys och syntes; []
   Keywords : 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;

   Abstract : 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. READ MORE

5. 3. C2- and C3-symmetric ligands via ring-opening of aziridines

   Author : Fredrik Lake; KTH; []
   Keywords : asymmetric catalysis; aziridine; benzaldehyde; diethylzinc; enantionselective; ligand; proazaphosphatrane; ring-opening; sulfonamide; symmetry; titanium; nicronium;

   Abstract : This thesis deals with the design and synthesis of chiralenantiopure nitrogencontaining ligands and the use of theseligands in asymmetric catalysis. A modular synthetic approachto enantiopure nitrogen-containing ligands was developed. Thesynthetic method is based on the ring-opening of activatedchiral aziridines by nitrogen nucleophiles. READ MORE

6. 4. Ring-opening catalysts for cetane improvement of diesel fuels

   Author : Ulf Nylén; Magali Boutonnet; Sven Järås; François Garin; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ring opening selective ; naphthenic structure; indan; light cycle oil LCO ; cetane; Pt-Ir catalyst; microemulsion; XPS; TPR; TEM; DRIFTS; sulphur analysis; GC-SCD; Chemical engineering; Kemiteknik;

   Abstract : The global oil refining industry with its present product distribution essentially shifted towards fuels such as gasoline and diesel will most likely hold the fort for considerable time. However, conditions are changing and refinery survival will very much depend on long-term planning, process and product flexibility and being at the frontiers of refining technology, a technology where catalysts play leading roles. READ MORE

7. 5. Synthesis of functional degradable polymers by radical ring-opening polymerization

   Author : Jenny Undin; Ann-Christine Albertsson; Mats Johansson; Monica Ek; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; tissue engineering; ring-opening polymerization; 2; 2´-azoisobutyronitrile; cyclic ketene acetals; 2-methylene- 1; 3; 6-trioxocane; 2-methylene- 1; 3-dioxepane; vinyl acetate; coopolymerization;

   Abstract : The increased demand for understanding cell-material interactions and subsequently create personalized implants for tissue engineering has resulted in an increased interest in developing new monomers with functional groups. The focus of the work presented in this thesis has been on the synthesis of functional monomers and the polymerization of these into functional amorphous aliphatic polyesters. READ MORE