Fabien Lachaud - Academia.edu (original) (raw)
Papers by Fabien Lachaud
Tetrahedron Letters, 2006
The synthesis of a salicylaldehyde derivative facing an encumbered phenol group on a naphthalene ... more The synthesis of a salicylaldehyde derivative facing an encumbered phenol group on a naphthalene block as a molecular shaft is reported. This molecular unit has been designed to elaborate coordinating ligands holding non-coordinating phenol group for the generation of phenoxyl radical in the close proximity of a metal complex.
The Journal of Physical Chemistry A, 2012
The properties of the ground and excited states of several porphyrins appended with external chel... more The properties of the ground and excited states of several porphyrins appended with external chelates coordinated to ruthenium-bisbipyridine units are reported. The important modification of the absorption spectrum upon coordination with the ruthenium complex showed that a significant electronic communication between the two subunits was present in the ground state. Experimental results were compared with quantum chemistry calculations performed at density functional theory and time-dependent density functional theory level. The influence of the exchange-correlation functional on the quality of the computed absorption spectrum is shown, and the better behavior of hybrid functionals over long-range corrected ones was rationalized. The excited states topology analysis, performed using natural transition orbitals, gave a more evident confirmation of the communication between the subunits and showed that these new compounds can be promising as dyes in dye-sensitized solar cells.
Tetrahedron Letters, 2012
The synthesis and characterization of a new family of ester protected N-substituted [1,4,7,10-tet... more The synthesis and characterization of a new family of ester protected N-substituted [1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (H3DO3A) derivatives containing a pendant thioctic acid (a lipoic acid, LA) are reported. These compounds (DO3A t Bu-NLA, DO3A t Bu-NMeNLA, and DO3A t Bu-NEtNLA) are suitable for the functionalization of gold surfaces with rare-earth complexes.
Dalton Transactions, 2012
Porphyrins bearing enaminoketones at their periphery have been used as ancillary ligands in ruthe... more Porphyrins bearing enaminoketones at their periphery have been used as ancillary ligands in ruthenium complexes. Free base, nickel and zinc porphyrins were successfully coordinated to Ru(bpy)(2)Cl(2) under microwave irradiation. The positive contribution of the ruthenium complex was demonstrated by the complexes' wide absorption domains that covered the 500-600 nm region where the parent porphyrins did not absorb. Electrochemical as well as computational data revealed an efficient electronic communication between the porphyrins and the ruthenium cation in the dyads.
Angewandte Chemie International Edition, 2005
Dalton Transactions, 2013
A new cyclen derivative L, bearing a methyl-chromeno-pyridinylidene hydrazone moiety, was synthes... more A new cyclen derivative L, bearing a methyl-chromeno-pyridinylidene hydrazone moiety, was synthesized and studied in MeOH, as potential fluorescent "OFF-on-ON" sensors for Zn(II). Photophysical properties of this ligand being PET regulated, L was only weakly emissive in the absence of metal ions (OFF). L fluorescence was increased modestly upon addition of one equivalent of Zn(II), and further increased upon addition of a second equivalent. Therefore, Zn : L behaved as a highly sensitive ON sensor for zinc. This efficiency was correlated to Zn(II) coordination via the hydrazone moiety of the fluorophore, producing an efficient CHelation-Enhanced Fluorescence (CHEF) effect. A complementary theoretical study carried out with DFT calculations further elucidated the optical properties.
Chemistry - A European Journal, 2007
Tetrahedron Letters, 2006
The synthesis of a salicylaldehyde derivative facing an encumbered phenol group on a naphthalene ... more The synthesis of a salicylaldehyde derivative facing an encumbered phenol group on a naphthalene block as a molecular shaft is reported. This molecular unit has been designed to elaborate coordinating ligands holding non-coordinating phenol group for the generation of phenoxyl radical in the close proximity of a metal complex.
The Journal of Physical Chemistry A, 2012
The properties of the ground and excited states of several porphyrins appended with external chel... more The properties of the ground and excited states of several porphyrins appended with external chelates coordinated to ruthenium-bisbipyridine units are reported. The important modification of the absorption spectrum upon coordination with the ruthenium complex showed that a significant electronic communication between the two subunits was present in the ground state. Experimental results were compared with quantum chemistry calculations performed at density functional theory and time-dependent density functional theory level. The influence of the exchange-correlation functional on the quality of the computed absorption spectrum is shown, and the better behavior of hybrid functionals over long-range corrected ones was rationalized. The excited states topology analysis, performed using natural transition orbitals, gave a more evident confirmation of the communication between the subunits and showed that these new compounds can be promising as dyes in dye-sensitized solar cells.
Tetrahedron Letters, 2012
The synthesis and characterization of a new family of ester protected N-substituted [1,4,7,10-tet... more The synthesis and characterization of a new family of ester protected N-substituted [1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (H3DO3A) derivatives containing a pendant thioctic acid (a lipoic acid, LA) are reported. These compounds (DO3A t Bu-NLA, DO3A t Bu-NMeNLA, and DO3A t Bu-NEtNLA) are suitable for the functionalization of gold surfaces with rare-earth complexes.
Dalton Transactions, 2012
Porphyrins bearing enaminoketones at their periphery have been used as ancillary ligands in ruthe... more Porphyrins bearing enaminoketones at their periphery have been used as ancillary ligands in ruthenium complexes. Free base, nickel and zinc porphyrins were successfully coordinated to Ru(bpy)(2)Cl(2) under microwave irradiation. The positive contribution of the ruthenium complex was demonstrated by the complexes' wide absorption domains that covered the 500-600 nm region where the parent porphyrins did not absorb. Electrochemical as well as computational data revealed an efficient electronic communication between the porphyrins and the ruthenium cation in the dyads.
Angewandte Chemie International Edition, 2005
Dalton Transactions, 2013
A new cyclen derivative L, bearing a methyl-chromeno-pyridinylidene hydrazone moiety, was synthes... more A new cyclen derivative L, bearing a methyl-chromeno-pyridinylidene hydrazone moiety, was synthesized and studied in MeOH, as potential fluorescent "OFF-on-ON" sensors for Zn(II). Photophysical properties of this ligand being PET regulated, L was only weakly emissive in the absence of metal ions (OFF). L fluorescence was increased modestly upon addition of one equivalent of Zn(II), and further increased upon addition of a second equivalent. Therefore, Zn : L behaved as a highly sensitive ON sensor for zinc. This efficiency was correlated to Zn(II) coordination via the hydrazone moiety of the fluorophore, producing an efficient CHelation-Enhanced Fluorescence (CHEF) effect. A complementary theoretical study carried out with DFT calculations further elucidated the optical properties.
Chemistry - A European Journal, 2007