METAL-LIGAND COOPERATION WITH NHC-PHOSPHONIUM YILDE PINCER COMPLEXES
CHEMISTRY & GREEN CHEMISTRY
Lab: LCC
Duration: NanoX master Internship (8 months part-time in-lab immersion)
Latest starting date: 02/01/2025
Localisation: LCC-CNRS – Toulouse, University Paul Sabatier
205 route de Narbonne – BP 44099
31077 Toulouse cedex 4 – FRANC
Supervisors:
Dmitry Valyaev dmitry.valyaev@lcc-toulouse.fr
Yves Canac yves.canac@lcc-toulouse.fr
This research master's degree project could be followed by a PhD
Work package:
Among the large variety of ligands available, carbon ligands have become essential,
especially with the emergence of N-heterocyclic carbenes (NHC). Phosphonium ylides (PY:
R3P+−CR2− <-> R3P=CR2), which represent an alternative class of carbon ligands act also as
effective Lewis bases in coordination chemistry. Electron-rich NHC-phosphonium ylide
Pd(II) complexes were thus recently prepared in the bidentate (A),1 and in the pincer series
(B),2 the latter being active in the catalytic allylation of aldehydes. In parallel, a bidentate
NHC-based Mn(I) complex (C) featuring a phosphonium ylide (PYr) bound in a reversed
fashion to the metal was reported to activate H2 through a new mode of metal-ligand
cooperation acting as one of the most efficient catalyst for ketone hydrogenation.3 More
recently, an ortho-metalated Pd(II) complex (D) containing such P-coordinated
phosphonium ylide was characterized.4 Based on these results, it is envisioned now to
prepare unprecedented pincer complexes E exhibiting NHC ligand N-substituted by two
phosphonium ylides, one ylide being bound to the metal in a conventional manner by its C-
atom to provide strong electron density and the other one in an unconventional manner
by its P-atom to bring non-innocent character. The synthesis of complexes E that maintain
a vacant coordination site could constitute a step forward in the design of new cooperative
carbon-based systems, from a fundamental point of view but also in the perspective of
catalytic applications (See corresponding illustration as attached file).
We are looking for a motivated candidate for this internship, which will take place in the
team “Molecular design of transition metal pre-catalysts” of the LCC-CNRS in Toulouse. The
realization of this internship will allow the candidate to acquire expertise in synthetic
organometallic chemistry, organic synthesis, homogeneous catalysis and various
spectroscopic methods.
References:
References:
[1]- I. Benaissa, R. Taakili, N. Lugan, Y. Canac, Dalton Trans. 2017, 46, 12293. [2]- (a) R. Taakili, C. Lepetit,
C. Duhayon, D. A. Valyaev, N. Lugan, Y. Canac, Dalton Trans. 2019, 48, 1709. (b) R. Taakili, C. Barthes, A.
Goeffon, C. Lepetit, C. Duhayon, D. A. Valyaev, Y. Canac, Inorg. Chem. 2020, 59, 7082. (c) M. El Kadiri, A.
Chihab, R. Taakili, C. Duhayon, D. A. Valyaev, Y. Canac, Organometallics 2022, 41, 456. [3]- (a) R. Buhaibeh,
O. A. Filippov, A. Bruneau-Voisine, J. Willot, C. Duhayon, D. A. Valyaev, N. Lugan, Y. Canac, J-B. Sortais
Angew. Chem. Int. Ed. 2019, 58, 6727. (b) (b) E. S. Gulyaeva, R. Buhaibeh, M. Boundor, K. Azouzi, J. Willot,
S. Bastin, C. Duhayon, N. Lugan, O. A. Filippov, J.-B. Sortais, D. A. Valyaev, Y. Canac, Chem. Eur. J. 2024, 30,
e202304201. [4]- M. Ameskal, R. Taakili, E. S. Gulyaeva, C. Duhayon, J. Willot, N. Lugan, C. Lepetit, D. A.
Valyaev, Y. Canac, Inorg. Chem. 2023, 62, 20129.
Areas of expertise:
Carbenes, ylides, ligand design, cooperativity, pincer complex, metal.
Synthetic chemistry, coordination chemistry, homogeneous catalysis, DFT
calculations.
Required skills for the internship:
Good knowledge in organic synthesis, organometallic chemistry, and advanced
characterization techniques (multinuclear NMR, X-Ray diffraction, MS, IR,...)