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Arnaud Boreux Aubin Lambion Dominic Campeau Marina Sanita Ruben Coronel Olivier Riant Fabien Gagosz 《Tetrahedron》2018,74(38):5232-5239
The synthesis of fluorinated synthetic intermediates has become a field of intense research in organic chemistry. In this article, we report the application of a gold-catalyzed rearrangement to the synthesis of β-trifluoromethylated α,β-unsaturated ketones. The scope of the reaction, as well as the valorization of the products in subsequent transformations has been investigated. This study allowed for the preparation of various CF3-substituted enones and fluorinated Diels-Alder adducts from easily accessible starting materials. 相似文献
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Vincent Knop André Nicolle Olivier Colin 《Proceedings of the Combustion Institute》2013,34(1):667-675
The present study extends the Nitrogen Oxide Relaxation Approach (NORA [Vervisch et al., Combust. Flame 158 (2011) 1480–1490]) for NOx modelling in engines by introducing alternative chemical routes to the thermal pathway as well as a speciation of nitrogen oxides into nitrogen monoxide (NO), nitrogen dioxide (NO2) and nitrous oxide (N2O). Perturbations of equilibrium state are considered to identify nitrogen oxide reactivity in various mixture and thermodynamic conditions. A common Intrinsic Low-Dimensional Manifold (ILDM) is identified for NO and NO2, while nitrous oxides appear to stay in near-equilibrium state for any in-cylinder conditions. The relaxations back towards the equilibrium state after the perturbations are analysed to extract the characteristic times of relaxation, an image of the species reactivity. Tabulation of equilibrium mass fractions and characteristic relaxation times as a function of mixture and thermodynamic conditions allows nitrogen oxide modelling to be performed for internal combustion engines at very low computational cost through idealised ILDMs that are independent of the combustion ones. Results show the accuracy of the modelling approach for nitrogen oxide emissions of a Diesel engine at part and full load. 相似文献
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Zahia Houiene Mounia Merabet-Khelassi Nassima Bouzemi Olivier Riant Louisa Aribi-Zouioueche 《Tetrahedron: Asymmetry》2013,24(5-6):290-296
Herein we report results of the chemoenzymatic deracemization of a range of secondary benzylic acetates 1a–9a via a sequence of hydrolysis with CAL-B lipase in non-conventional media, combined with esterification of the recovered alcohol according to the Mitsunobu protocol following an enzymatic kinetic resolution (KR). The KR of racemic acetates 1a–9a via an enzymatic hydrolysis, with CAL-B lipase and Na2CO3, in non-aqueous media was optimized and gave high selectivities (E ? 200) at good conversions (C >49%) for all of the substrates studied. This method competes well with the traditional one performed in a phosphate buffer solution. The deracemization using Mitsunobu inversion gave the (S)-acetates in moderate to excellent enantiomeric excess 75% < ee < 99%, in acceptable isolated yields 70% < yield < 89%, and with some variations according to the acetate structure. 相似文献
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