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11.
Back Cover: Large‐Scale Synthesis of Helicene‐Like Molecules for the Design of Enantiopure Thin Films with Strong Chiroptical Activity (Chem. Eur. J. 10/2016) 下载免费PDF全文
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Large‐Scale Synthesis of Helicene‐Like Molecules for the Design of Enantiopure Thin Films with Strong Chiroptical Activity 下载免费PDF全文
Dr. Amina Bensalah‐Ledoux Delphine Pitrat Thibault Reynaldo Dr. Monika Srebro‐Hooper Barry Moore II Prof. Jochen Autschbach Dr. Jeanne Crassous Prof. Stéphan Guy Dr. Laure Guy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3333-3346
Helicenes are fascinating molecules owing to their unusual properties and applications in many fields from catalysis to organic electronics. Herein, we report a straightforward pathway for the synthesis of helicene‐like molecules on a gram scale in an enantiopure form. Thin‐film materials with good propagating optical properties and very high chiroptical responses have been grown by using pulsed laser ablation without altering the structure or the enantiopurity of the molecules. Moreover, electronic and vibrational circular dichroism spectroscopies coupled with theoretical calculations enabled some dependences of the chiroptical properties with the structure to be highlighted, for example, effects of rigidification, aromatization, or the state of matter (liquid versus solid). 相似文献
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Thibault Dutronc Dr. Emmanuel Terazzi Dr. Laure Guénée Kerry‐Lee Buchwalder Aurore Spoerri Dr. Daniel Emery Dr. Jiri Mareda Dr. Sébastien Floquet Prof. Claude Piguet 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(26):8447-8456
This work illustrates how minor structural perturbations produced by methylation of 4′‐(dodecyloxy)‐4‐cyanobiphenyl leads to enthalpy–entropy compensation for their melting processes, a trend which can be analyzed within the frame of a simple intermolecular cohesive model. The transformation of the melting thermodynamic parameters collected at variable temperatures into cohesive free‐energy densities expressed at a common reference temperature results in a novel linear correlation, from which melting temperatures can be simply predicted from molecular volumes. 相似文献
14.
Emmanuelle Dubost Silvia Stiebing Thibault Ferrary Thomas Cailly Frédéric Fabis Valérie Collot 《Tetrahedron》2014
A set of variously substituted indazoles and hetero-aromatic derivatives were synthesized from o-halo-(het)arylaldehydes using a palladium catalyzed amination followed by cyclization. Starting from phenones, this process was extended to give 3-substituted indazoles. Moreover, N-1-substituted-indazoles can be reached by this strategy using an optional selective N-1-alkylation step during the process. This methodology offers a general and easy route for the synthesis of regioselectively substituted indazoles. 相似文献
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F. Thibault K.A. Grabow C.I. Marcus L.A. Robertson M.C. Stoffel 《Journal of Molecular Spectroscopy》2009,256(1):17-2081
Theoretical and experimental values have been determined for the pressure broadening of the ν1 + ν3 band of acetylene by hydrogen and deuterium at 195 K, and experimental values of the pressure shifts have been determined. Theoretical values have been calculated on the basis of a recent potential energy surface using the close coupling scheme. We discuss the detailed contribution of the various rotational angular momenta of the perturbing gas and the ortho and para contribution to the total pressure broadening cross-sections. We give routes to circumvent the computational cost of such calculations. Experimental values have been measured using a tunable diode laser spectrometer assuming a Voigt line shape. These pressure broadening parameters are compared with measurements performed recently at room temperature and with present measurements performed at 195 K in the ν1 + ν3 band of acetylene. A satisfactory agreement is obtained with the present results and available ones at 295 K. 相似文献
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Vincent Martin Thibault Le Bourdon Alexander Mattioli Pasqual 《Journal of sound and vibration》2011,330(17):4233-797
Acoustical holography can be used to identify the vibration velocity of an extended vibrating body. Such an inverse problem relies on the radiated acoustic pressure measured by a microphone array and on an a priori knowledge of the way the body radiates sound. Any perturbation on the radiation model leads to a perturbation on the velocity identified by the inversion process. Thus, to obtain the source vibration velocity with a good precision, it is useful to identify also an appropriate propagation model. Here, this identification, or adaptation, procedure rests on a geometrical interpretation of the acoustic holography in the objective space (here the radiated pressure space equipped with the L2-norm) and on a genetic algorithm.The propagator adaptation adds information to the holographic process, so it is not a regularisation method, which approximates the inverse of the model but does not affect the model. Moreover regularisations act in the variables space, here the velocities space. It is shown that an adapted model significantly decreases the quantity of regularisation needed to obtain a good reconstructed velocity, and that model adaptation improves significantly the acoustical holography results.In the presence of perturbations on the radiated pressure, some indications will be given on the interest or not to adapt the model, again thanks to the geometrical interpretation of holography in the objective space.As a numerical example, a disc whose vibration velocity on one of its sides is identified by acoustic holography is presented. On an industrial scale, this problem occurs due to the noise radiated by car wheels. The assessment of the holographic results has not yet been rigorously performed in such situations due to the complexity of the wheel environment made up of the car body, road and rolling conditions. 相似文献
19.
A note on subdifferentials of convex composite functionals 总被引:1,自引:0,他引:1
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