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1.
Angew Chem Int Ed Engl ; 55(11): 3785-9, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26880039

RESUMO

Copper-catalyzed Si-H, B-H, P-H, S-H, and N-H insertion reactions of 2,2,2-trifluoro-1-diazoethane and 1-aryl 2,2,2-trifluorodiazoethanes generated a large number of new fluorine-containing chemical entities for medicinal chemists. With selected Si-H and B-H insertion reactions, we demonstrate successful extension to asymmetric catalysis.

2.
Chemistry ; 20(50): 16694-706, 2014 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-25327947

RESUMO

An easy and versatile Cu-catalyzed propargylic substitution process is presented. Using easily prepared prochiral dichloro substrates, readily available Grignard reagents together with catalytic amount of copper salt and chiral ligand, we accessed a range of synthetically interesting trisubstituted chloroallenes. Substrate scope and nucleophile scope are broad, providing generally high enantioselectivity for the desired 1,3-substitution products. The enantioenriched chloroallenes could be further transformed into the corresponding trisubstituted allenes or terminal alkynes bearing all-carbon quaternary stereogenic centers, through the copper-catalyzed enantiospecific 1,1/1,3-substitutions. The two successive copper-catalyzed reactions could be eventually combined into a one-pot procedure and different desired allenes or alkynes were obtained respectively with high enantiomeric excesses.

3.
Angew Chem Int Ed Engl ; 52(51): 13642-6, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24346945

RESUMO

AAA: The asymmetric allylic alkylation (AAA) of trisubstituted cyclic allyl bromides with Grignard reagents is catalytic (2 mol % of ligand) and regioselective (SN 2'/SN 2=91:9→100:0). The quaternary carbon centers are formed with good to high enantioselectivity (e.r.=81.5:19.5→96:4).

4.
BMC Emerg Med ; 13: 3, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23496830

RESUMO

BACKGROUND: In the metropolitan area of Florence, 62% of major traumas involve powered two wheeler rider and pillion passengers, 10% cyclists, and 7% pedestrians. The urban and extra-urban areas are the most dangerous for the vulnerable road user. In-depth investigations are needed for assessing detailed information on road accidents. This type of study has been very limited in time frame in Italy, and completely absent in the Tuscan region.Consequently a study called "In-depth Study of road Accident in FlorencE" (In-SAFE) has been initiated. METHODS: A network between the Department of Mechanics and Industrial Technologies (University of Florence) and the Intensive Care Unit of the Emergency Department (Careggi Teaching Hospital, Florence) was created with the aim of collecting information about the road accidents. The data collected includes: on-scene data, data coming from examination of the vehicles, kinematics and dynamic crash data, injuries, treatment, and injury mechanisms. Each injury is codified thorough the AIS score, localized by a three-dimensional human body model based on computer tomography slices, and the main scores are calculated. We then associate each injury with its cause and crash technical parameters. Finally, all the information is collected in the In-SAFE database. RESULTS: Patient mean age at the time of the accident was 34.6 years, and 80% were males. The ISS mean is 24.2 (SD 8.7) and the NISS mean is 33.6 (SD 10.5). The main road accident configurations are the "car-to-PTW" (25%) and "pedestrian run over" (17,9%). For the former, the main collision configuration is "head-on crash" (57%). Cyclists and PTW riders-and-pillions-passengers suffer serious injuries (AIS3+) mainly to the head and the thorax. The head (56.4%) and the lower extremities (12.7%) are the most frequently injured pedestrian body regions. CONCLUSIONS: The aim of the project is to create an in-depth road accident study with special focus on the correlation between technical parameters and injuries. An in-depth investigation team was setup and is currently active in the metropolitan area of Florence.Twenty-eight serious road accidents involving twenty-nine ICU patients are studied. PTW users, cyclist and pedestrians are the most frequently involved in metropolitan accidents.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Simulação por Computador , Serviço Hospitalar de Emergência , Feminino , Humanos , Imageamento Tridimensional , Escala de Gravidade do Ferimento , Unidades de Terapia Intensiva , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Veículos Automotores/estatística & dados numéricos , Distribuição por Sexo , Tomografia Computadorizada por Raios X , População Urbana , Adulto Jovem
5.
Chemistry ; 19(4): 1466-75, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23225369

RESUMO

The Cu-free asymmetric allylic alkylation, catalysed by NHC, with Grignard reagents is reported on allyl bromide derivatives with good results. The enantioselectivity was quite homogeneous (around 85% ee) on large and various substrates, regardless of the nature of the Grignard reagent. The formation of stereogenic quaternary centres was highly regioselective for both aliphatic and aromatic derivatives with good enantiomeric excess (up to 92% ee). The methodology developed was found to be complementary with the Cu-catalysed version. Several new NHCs were tested with improved efficiency. In addition, mechanistic studies, using NMR spectroscopy, led to the discovery of the catalytically active species.

6.
Chem Commun (Camb) ; 48(93): 11404-6, 2012 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-23085621

RESUMO

A valuable Cu-free protocol is reported where an NHC ligand has been employed to form quaternary carbon centers bearing fluoroalkyl units. The results obtained, from this allylic substitution, are better in terms of enantioselectivity and regioselectivity compared to the copper catalyzed system.

7.
Org Lett ; 14(6): 1568-71, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22394218

RESUMO

A series of substrates containing a vinylic bromide were employed in a copper-free methodology using bidendate NHC ligands. The desired compounds are generally obtained with good enantioselectivity and good regioselectivity. Importantly the copper-catalyzed system afforded a lower enantioselectivity value. The catalytic products could be transformed into a broad scope of new 1,1-disubstituted olefins in a single step transformation without erosion of the enantioselectivity.

8.
Chem Commun (Camb) ; 48(10): 1604-6, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22159525

RESUMO

Two complementary artificial diether phospholipids were synthesized that can undergo a Cu(I)-catalyzed Huisgen-Sharpless click reaction. The resulting lipid can bridge the membranes of large unilamellar vesicles and cause their aggregation and ultimately their fusion.


Assuntos
Fosfolipídeos/química , Triazóis/química , Catálise , Química Click , Cobre/química , Estrutura Molecular , Tamanho da Partícula , Fosfolipídeos/síntese química , Propriedades de Superfície
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