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40. Bidentate Oxazoline-Imine Ruthenium(II) Complexes: Intermediates in 2 the Methanolysis/Hydration of Nitrile Groups

Author

Ben Ammar, H., Miao, Xiaowei, Fischmeister, Cédric, Toupet, Loïc, Dixneuf, Pierre H., laboratoire de chimie organique appliquée, Faculté des sciences de Gabes, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.CATA]Chemical Sciences/Catalysis
Abstract

International audience; The reaction of [RuCl2(p-cymene)]2 with benzoxazoleacetonitriles and NH4+BF4− in methanol leads to bidentate N,N′-benzoxazole-methoxyimine-ruthenium(II) complexes 7, corresponding to the addition of methanol to the ruthenium(II)-activated nitrile triple bond. The X-ray structure of a complex 7 shows equivalent Ru−N and slightly different C═N bond distances. The catalytic hydration of benzoxazolacetonitriles with [RuCl2(p-cymene)]2 in methanol/water leads to quantitative formation of corresponding amides under mild conditions.

Published
2010
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42. Synthesis of chiral 2-cyanomethyl oxazolines and their applications in ruthenium-catalyzed allylic substitution

Author

Youssef, C., Ben Ammar, H., Ben Salem, R., Bruneau, Christian, Dixneuf, Pierre H., laboratoire de chimie organique physique, Faculté des Sciences de Sfax, Université de Sfax - University of Sfax-Université de Sfax - University of Sfax, laboratoire de chimie organique appliquée, Faculté des sciences de Gabes, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.CATA]Chemical Sciences/Catalysis, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2009

43. Gallium incorporation in InAlN: role of the chamber design and history, and the effects of growth pressure.

Author

Ben Ammar, H., Minj, A., Gamarra, P., Lacam, C., Tordjman, M., di Forte‐Poisson, M. A., Morales, M., Chauvat, M. P., and Ruterana, P.

Subjects
*ALUMINUM nitrate, *GALLIUM nitride, *METAL organic chemical vapor deposition, *X-ray spectroscopy, *INTERMEDIATES (Chemistry), *THICKNESS measurement
Abstract

In this work, we have investigated the non-intentional incorporation of gallium in InAlN layers grown by metal organic vapor phase epitaxy (MOVPE) using two reactors. Atomic force microscopy (AFM) and electron dispersive X-ray spectroscopy (EDS) have been used to characterize the surface morphology and the atomic composition of InAl(Ga)N/GaN structures. The horizontal chamber systematical produces pure ternary layers whereas the close coupled shower head vertical chamber can lead to quaternary alloys. Cleaning the latter significantly reduces the amount of gallium to 1% in the epilayers. Moreover, we show an alternative way to reduce the amount gallium: the use of an intermediate growth pressure typically around 80 Torr drops the inclusion of gallium to 6%. In the presence of such amount of Ga, the growth process appears to be modified and there is a competition between In and Ga for their incorporation, and the Al composition is systematically reduced. The morphology of the layers is also observed to suffer, with the formation of large and closed trenches toward a possible three dimensional growth mode when the layer thickness is increased. [ABSTRACT FROM AUTHOR]

Published
2017
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