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1. 1. Catalytic Asymmetric Ketone and Alkene Reductions Using Transition Metal Complexes

   Författare :Klas Källström; Pher Andersson; Per Arvidsson; Jonathan Williams; Uppsala universitet; []
   Nyckelord :Organic chemistry; Catalytic; Asymmetric; Reductions; Ketones; Alkenes; Transition metal; Complexes; Organisk kemi;

   Sammanfattning : This thesis contains seven papers dealing with iridium and ruthenium based catalytic asymmetric reductions, either of ketones into chiral alcohols, or olefins into chiral alkanes. The first part of the thesis describes how we have designed and evaluated new bicyclic ligands containing either N,S or N,N chelating atoms. LÄS MER

3. 2. Downsizing: Personnel Reductions at the Swedish Tobacco Monopoly, 1915-1939

   Författare :Tobias Karlsson; Ekonomisk-historiska institutionen; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; severance pay; human capital; internal labour markets; economic history; tobacco industry; state-owned enterprises; the Swedish Tobacco Monopoly; the Swedish Tobacco Workers’ Union; gender; male-breadwinner norm; mechanization; workforce reductions; hours-reductions; layoffs; inter-war period;

   Sammanfattning : Downsizing is a phenomenon that remarkably seldom has been the subject of historical inquiry. This study investigates how a state-owned enterprise, the Swedish Tobacco Monopoly, reduced its labour inputs because of changed consumer preferences and mechanization in the 1920s and 1930s. LÄS MER

4. 3. Asymmetric Hydrogenations : Syntheses of Ligands and Expansion of Substrate Scope

   Författare :Pradeep Cheruku; Pher Andesson; Jay Siegel; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Catalysis; Asymmetric; Hydrogenations; Reductions; Olefins; Imines; Enol phosphinates; Transition metal; Complexes; Iridium; Enamines; Ruthenium; Ligands; Trifluoromethyl; Diphenylvinylphosphine oxides; Vinyl phosphonates; Chemistry; Kemi;

   Sammanfattning : Asymmetric hydrogenation has emerged as a versatile methodology to obtain a wide range of chiral precursors. This thesis focused on the synthesis of new chiral ligands and the expansion of the substrate scope of asymmetric hydrogenations. LÄS MER

5. 4. Asymmetric Hydrogenations of Imines, Vinyl Fluorides, Enol Phosphinates and Other Alkenes Using N,P-Ligated Iridium Complexes

   Författare :Jarle Sidney Diesen; Pher G. Andersson; Kálmán J. Szabó; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Organic chemistry; Catalysis; Asymmetric; Hydrogenations; Reductions; Alkenes; Imines; Vinyl fluorides; Enolphosphinates; Transition metal; Complexes; Iridium; Organisk kemi; Chemistry; Kemi;

   Sammanfattning : The research described in this thesis is directed toward the efficient, enantioselective synthesis of chiral products that have useful functionality. This goal was pursued through catalytic asymmetric hydrogenation, a reaction class that selectively introduces one or two stereocenters into a molecule in an atom-efficient step. LÄS MER

7. 5. Synthesis and Studies of NADH Models: Stereoselective Reductions and Host-Guest Properties

   Författare :Ulrik Gran; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; synthesis; NADH model; host-guest complex; stereoselective reductions; macrocyclic; reducing agent;

   Sammanfattning : The aim of the project has been to synthesise macrocyclic NADH models and to study them as reducing agents and hosts. Three types of macrocyclic NADH models have been synthesised. They consist of the same subunits; a chiral unit, a nicotinamide unit and an aromatic spacer. LÄS MER