On the Mechanism of the Copper-Catalyzed Enantioselective 1,4-Addition of Grignard Reagents to α,β-Unsaturated Carbonyl Compounds

The mechanism of the enantioselective 1,4-addition of Grignard reagents to α,β-unsaturated carbonyl compounds promoted by copper complexes of chiral ferrocenyl diphosphines is explored through kinetic, spectroscopic, and electrochemical analysis. On the basis of these studies, a structure of the active catalyst is proposed. The roles of the solvent, copper halide, and the Grignard reagent have been examined. Kinetic studies support a reductive elimination as the rate-limiting step in which the chiral catalyst, the substrate, and the Grignard reagent are involved. The thermodynamic activation parameters were determined from the temperature dependence of the reaction rate. The putative active species and the catalytic cycle of the reaction are discussed.

Prospective study of asbestos-related diseases incidence cases in primary health care in an area of Barcelona province

<p>Abstract</p> <p>Background</p> <p>Asbestos related diseases include a number of conditions due to inhalation of asbestos fibres at work, at home or in the environment, such as pleural mesothelioma, asbestosis and calcified pleural plaques. Few epidemiological studies have established the incidence of asbestos related diseases in our area. The present proposal is based on a retrospective study externally funded in 2005 that is currently taking place in the same area and largely carried out by the same research team.</p> <p>The aim of the study is to achieve a comprehensive and coordinated detection of all new cases of Asbestos Related Diseases presenting to primary care practitioners.</p> <p>Methods/design</p> <p>This is a multicentre, multidisciplinary and pluri-institutional prospective study.</p> <p><b>Setting</b></p> <p>12 municipalities in the Barcelona province within the catchment area of the health facilities that participate in the study.</p> <p><b>Sample</b></p> <p>This is a population based study, of all patients presenting with diseases caused by asbestos in the study area.</p> <p><b>Measurements</b></p> <p>A clinical and epidemiological questionnaire will be filled in by the trained researchers after interviewing the patients and examining their clinical reports.</p> <p>Discussion</p> <p>Data on the incidence of the different Asbestos Related Diseases in this area will be obtained and the most plausible exposure source and space-time-patient profile will be described. The study will also improve the standardization of patient management, the coordination between health care institutions and the development of preventive activities related with asbestos exposure and disease.</p

CCDC 610501: Experimental Crystal Structure Determination

Related Article: S.R.Harutyunyan, F.Lopez, W.R.Browne, A.Correa, D.Pena, R.Badorrey, A.Meetsma, A.J.Minnaard, B.L.Feringa|2006|J.Am.Chem.Soc.|128|9103|doi:10.1021/ja0585634,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

CCDC 610500: Experimental Crystal Structure Determination

Related Article: S.R.Harutyunyan, F.Lopez, W.R.Browne, A.Correa, D.Pena, R.Badorrey, A.Meetsma, A.J.Minnaard, B.L.Feringa|2006|J.Am.Chem.Soc.|128|9103|doi:10.1021/ja0585634,Related Article: F.Caprioli,M.Lutz,A.Meetsma,A.J.Minnaard,S.R.Harutyunyan|2013|Synlett|24|2419|doi:10.1055/s-0033-1339851,An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Asymmetric organocatalytic reactions by bifunctional amine-thioureas

10.1039/c1cy00271fCatalysis Science and Technology181298-131