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1.
Marc Visseaux Mickael Terrier Andr Mortreux Pascal Roussel 《Comptes Rendus Chimie》2007,10(12):1195-1199
The reaction of one equivalent of Nd(BH4)3(THF)3 with an half equivalent of dialkylmagnesium in the presence of a stoichiometric amount of pentamethylcyclopentadiene cleanly affords a new kind of half-sandwich of neodymium that is stable toward comproportionation. This strategy can be advantageously applied to generate in situ catalysts allowing the controlled polymerisation of isoprene. 相似文献
2.
Eric Monflier Sbastien Tilloy Georges Fremy Yves Castanet Andr Mortreux 《Tetrahedron letters》1995,36(52):9481-9484
Solvent free biphasic hydroformylalion of various water-insoluble terminal olefins can be achieved in high yields and sclcctivitics by using a water-soluble rhodium/triphenylphosphine trisulfonate catalyst and per(2,6-di-o-mclhyl)-β-cyclodcxtrin as inverse phase transfer catalyst. The catalytic activities were up to ten times higher than those observed without pcr(2,6-di-o-methyl)-β-cyclodextrin. 相似文献
3.
Summary. Total positivity is an important concept which has been studied by Gantmacher, Karlin and Schoenberg. In section 1, new properties
of totally positive functions are given. The concept of totally monotonic families of sequences (TMFS), by mean of positivity
of some determinant, is defined and studied.
Applications to extrapolation algorithms are given.
Received October 22, 1997 / Revised version received April 14, 1998 / Published online August 19, 1999 相似文献
4.
We became aware, in the course of our on-going research, that the number-average molecular weight of poly(1,4-trans isoprene) determined by conventional gel permeation chromatography (GPC) in tetrahydrofuran (THF) using polystyrene standards differs from its true value by a factor 2. As far as we know, the Mark-Houwink coefficients of this polymer in a widespread GPC eluent such as THF have never been determined. We provide in this contribution a simple relationship between the number-average molecular weight of poly(1,4-trans isoprene) determined by GPC in THF using polystyrene standards and its true value. 相似文献
5.
Philippe Zinck Andreia Valente Fanny Bonnet Ana Violante André Mortreux Marc Visseaux Simona Ilinca Rob Duchateau Pascal Roussel 《Journal of polymer science. Part A, Polymer chemistry》2010,48(4):802-814
The ability of various rare earth borohydride and chloride complexes/n‐butylethylmagnesium systems to operate styrene chain transfer polymerization in mild conditions has been assessed. Thirteen precatalysts have been considered: the rare earth trisborohydrides Ln(BH4)3(THF)x (x = 3, Ln = Nd (1), La (2), Sm (3), x = 2, Ln = Y (4), Sc (5)), the rare earth chlorides LnCl3(THF)x (x = 3, Ln = Nd (6), La (7), Sm (8), Y (9), x = 2, Ln = Sc (10)), the mixed La(BH4)2Cl(THF)2.6 (11) and the half‐lanthanidocenes Cp*Ln(BH4)2(THF)2 (Ln = Nd (12), La (13)). Six systems were found to be active precatalysts for the polymerization of styrene. 1 , 2 , and 11 led to an efficient transmetalation of the growing polystyrene chain with the simultaneous occurrence of βH elimination, whereas 7 , 12 , and 13 led to catalyzed chain growth behavior. It is noteworthy that the catalyzed chain growth obtained with 12 and 13 occurs with significant stereoselectivity. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 802–814, 2010 相似文献
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7.
Lai J Molinier V Sauthier M Moity L Castanet Y Mortreux A Aubry JM 《Langmuir : the ACS journal of surfaces and colloids》2012,28(1):242-250
2,7-Octadienyl ethers of tri- and tetraethylene glycol (C(8:2)E(3) and C(8:2)E(4)) have been synthesized by the atom-economical butadiene telomerization of the corresponding poly(ethylene glycols). On one hand, this synthetic path is attractive because it is expeditious and environmentally benign, and on the other hand, it provides unconventional amphiphiles for which the lipophilic chains possess two double bonds. These two unsaturations increase the global hydrophilicity of the compound, which is also highlighted by the modelization of the compounds using the conductor-like screening model for real solvents (COSMO-RS). The behavior of C(8:2)E(3) and C(8:2)E(4) in binary amphiphile/water and ternary amphiphile/oil/water systems is therefore greatly modified compared to that of the conventional fully saturated homologues (C(8)E(3) and C(8)E(4)) that are easily obtained after hydrogenation. This results in a lowered efficiency of the unsaturated compounds for oil solubilization. The usual Winsor-type microemulsion systems are formed, and for the same oil, the DLS investigation of the microstructure of the Winsor I microemulsion does not highlight any difference in the self-association between the unsaturated and saturated compounds. 相似文献
8.
Mortreux 《Fresenius' Journal of Analytical Chemistry》1865,4(1):259
Ohne Zusammenfassung 相似文献
9.
M. Mortreux 《Fresenius' Journal of Analytical Chemistry》1862,1(1):390-391
Ohne Zusammenfassung 相似文献
10.
Sueur B Leclercq L Sauthier M Castanet Y Mortreux A Bricout H Tilloy S Monflier E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(21):6228-6236
A new class of cationic alpha-cyclodextrins bearing 2-hydroxy-3-trimethylammoniopropyl groups has been synthesised. We investigated their efficiency as mass-transfer promoters in a biphasic hydroformylation reaction catalysed by a rhodium trisulfonated triphenylphosphine system. These cationic alpha-cyclodextrins greatly increased the reaction rate, the chemoselectivity, and, surprisingly, the linear-to-branched aldehyde ratio. We attributed this unexpected enhancement of the linear-to-branched aldehyde ratio to the in situ formation of new catalytic supramolecular species obtained by ion-exchange between the catalyst ligand and the cationic alpha-cyclodextrins. 相似文献