0000000000524042
AUTHOR
Alexandre Massard
Titanium imido complexes stabilised by bis(iminophosphoranyl)methanide ligands: the influence of N-substituents on solution dynamics and reactivity
Terminal titanium imido complexes of the general formula [Ti(N(t)Bu)Cl{CH(Ph2PNR)2}] 4 (R = Ph, (i)Pr, (t)Bu) are reported. These compounds were synthesized from the corresponding Li adducts 3 of BIPMH (bis(iminophosphoranyl)methanide) and Mountford's complex [Ti(N(t)Bu)Cl2(Py)3]. The crystal structures of two of the Ti complexes (R = Ph, (t)Bu) and two of the Li compounds (R = (i)Pr, (t)Bu) are reported. Dynamic solution NMR spectroscopy reveals a dynamic isomerisation process in the case of the Ti complex 4c (R = (t)Bu). DFT studies showed that this dynamic process comes from steric repulsion between the imido ligand and the (t)Bu N-substituents on the BIPMH ligand. Complexes 4 were teste…
Assessment of Catalysis by Arene‐Ruthenium Complexes Containing Phosphane or NHC Groups bearing Pendant Conjugated Diene Systems
Two p-cymene-ruthenium complexes 1 and 2 were isolated in high yields by treating the [RuCl2(p-cymene)]2 dimer with new hybrid phosphane- or NHC-linked diene ligands. Both complexes were fully characterized by NMR spectroscopy, and the molecular structure of the ruthenium–p-cymene complex 1, containing the phosphane–diene ligand system, was determined by X-ray diffraction analysis. The catalytic activities of both compounds were probed in atom-transfer radical addition (ATRA) and polymerization (ATRP), in the cyclopropanation of olefins, in the ring-opening metathesis polymerization (ROMP) of norbornene, and in the synthesis of enol esters from hex-1-yne and 4-acetoxybenzoic acid.
(Cycloheptadienyl)diphenylphosphine: A Versatile Hybrid Ligand
(3,5-Cycloheptadienyl)diphenylphosphine is easily synthesized from the reaction of diphenylphosphine with 1,3,5-cycloheptatriene. This new phosphine-diene has been coordinated as a monodentate P ligand with Pt, Pd, Au, Ni, and Ru; as a bidentate (P, olefin) ligand with Pt and Pd; and as a tridentate (P, diene) ligand with Rh. Fluxional properties of several complexes have been studied via NMR experiments and theoretical consideration.
Development of Bimetallic Titanocene−Ruthenium−Arene Complexes As Anticancer Agents: Relationships between Structural and Biological Properties
A series of bimetallic titanium-ruthenium complexes of general formula [(η(5)-C(5)H(5))(μ-η(5):κ(1)-C(5)H(4)(CR(2))(n)PR'R'')TiCl(2)](η(6)-p-cymene)RuCl(2) (n = 0, 1, 2 or 4; R = H or Me; R' = H, Ph, or Cy; R'' = Ph or Cy) have been synthesized, including two novel compounds as well as two cationic derivatives of formula [(η(5)-C(5)H(5))(μ-η(5):κ(1)-C(5)H(4)(CH(2))(n)PPh(2))TiCl(2)] [(η(6)-p-cymene)RuCl](BF(4)) (n = 0 or 2). The solid state structure of two of these compounds was also established by X-ray crystallography. The complexes showed a cytotoxic effect on human ovarian cancer cells and were markedly more active than their Ti or Ru monometallic analogues titanocene dichloride and RA…
Ligands hybrides : synthèse et chimie de coordination
This manuscript deals with the synthesis of hybrids ligands and their coordination ability. The first part is dedicated to Cp-imidazole, Cp-imidazolium and Cp-phosphine ligands. Several synthetic routes have been developed to reach these mixed ligands and their coordination chemistry has been studied with titanium. In a second part, a method developed in our laboratory to synthesize phosphine-olefines was applied to obtain a phosphino-diene bearing three potential coordination sites. We have studied the coordination modes of this hybrid ligand using various transition metals and some of the formed complexes were tested in catalysis. In the third part is described the coordination chemistry …
A Simple Phosphine–Diolefin‐Promoted Copper‐Catalysed N‐Arylation of Pyrazoles with (Hetero)aromatic Bromides: The Case of Chloroarenes Revisited
A molecularly defined new phosphine–diolefin cubane copper pre-catalyst used at 1.25 mol % under mild conditions promotes the coupling of pyrazoles to functionalised aryl and heteroaryl bromides, which hold a variety of functional groups. This versatile phosphorus-based system was thus successfully used, under identical conditions, for the coupling of a large scope of heteroaromatics to selectively produce pyridinyl- and pyrimidinyl-pyrazoles, as well as several novel furyl-, thienyl- and thiazolyl-substituted pyrazoles. The careful investigation of coupling with the analogous aryl and heteroaryl chlorides clearly indicated that for specifically activated chloroarenes a direct nucleophilic …
CCDC 987356: Experimental Crystal Structure Determination
Related Article: Adrien T. Normand, Alexandre Massard, Philippe Richard, Coline Canovas, Cédric Balan, Michel Picquet, Audrey Auffrant, Pierre Le Gendre|2014|Dalton Trans.|43|15098|doi:10.1039/C4DT00746H
CCDC 881688: Experimental Crystal Structure Determination
Related Article: Vincent Rampazzi, Alexandre Massard, Philippe Richard, Michel Picquet, Pierre Le Gendre, Jean-Cyrille Hierso|2012|ChemCatChem|4|1828|doi:10.1002/cctc.201200368
CCDC 987359: Experimental Crystal Structure Determination
Related Article: Adrien T. Normand, Alexandre Massard, Philippe Richard, Coline Canovas, Cédric Balan, Michel Picquet, Audrey Auffrant, Pierre Le Gendre|2014|Dalton Trans.|43|15098|doi:10.1039/C4DT00746H
CCDC 987357: Experimental Crystal Structure Determination
Related Article: Adrien T. Normand, Alexandre Massard, Philippe Richard, Coline Canovas, Cédric Balan, Michel Picquet, Audrey Auffrant, Pierre Le Gendre|2014|Dalton Trans.|43|15098|doi:10.1039/C4DT00746H
CCDC 987358: Experimental Crystal Structure Determination
Related Article: Adrien T. Normand, Alexandre Massard, Philippe Richard, Coline Canovas, Cédric Balan, Michel Picquet, Audrey Auffrant, Pierre Le Gendre|2014|Dalton Trans.|43|15098|doi:10.1039/C4DT00746H
CCDC 1056295: Experimental Crystal Structure Determination
Related Article: Johann Baraut, Alexandre Massard, Florian Chotard, Ewen Bodio, Michel Picquet, Philippe Richard, Yannick Borguet, François Nicks, Albert Demonceau, Pierre Le Gendre|2015|Eur.J.Inorg.Chem.||2671|doi:10.1002/ejic.201500054
CCDC 1023384: Experimental Crystal Structure Determination
Related Article: Johann Baraut, Alexandre Massard, Florian Chotard, Ewen Bodio, Michel Picquet, Philippe Richard, Yannick Borguet, François Nicks, Albert Demonceau, Pierre Le Gendre|2015|Eur.J.Inorg.Chem.||2671|doi:10.1002/ejic.201500054