Search results for "phosphonium"
showing 10 items of 168 documents
Exploring reactivity of a bis-sulfonium zirconocene-ate dimer: synthesis of various zwitterionic phosphonium anionic zirconocene complexes
2007
Abstract Formal [3+2] cycloaddition reactions between the bis-sulfonium zirconocene-ate dimer 1a and methylpropiolate, benzaldehyde and carbon disulfide afforded stable zwitterionic phosphonium zirconocene-ate complexes 2–4, respectively, with two orthocondensed five-membered heterocycles. X-ray crystal structure of 4 has been determined. Elemental chalcogens (S, Se, Te) gave rise also to a new variety of five-coordinate zirconium(IV) complexes (5–7) by a formal [3+1] cycloaddition reaction. In these bicyclic zirconates, sulfur is included in a five-membered ring while the second chalcogen is in a four-membered one.
CCDC 245542: Experimental Crystal Structure Determination
2005
Related Article: L.Toma, R.Lescouezec, J.Vaissermann, P.Herson, V.Marvaud, F.Lloret, M.Julve|2005|New J.Chem.|29|210|doi:10.1039/b413473g
CCDC 809140: Experimental Crystal Structure Determination
2011
Related Article: O.Schott, J.Ferrando-Soria, A.Bentama, S.-E.Stiriba, J.Pasan, C.Ruiz-Perez, M.Andruh, F.Lloret, M.Julve|2011|Inorg.Chim.Acta|376|358|doi:10.1016/j.ica.2011.06.039
CCDC 989261: Experimental Crystal Structure Determination
2014
Related Article: Maria-Gabriela Alexandru, Diana Visinescu, Nadia Marino, Giovanni De Munno, Julia Vallejo, Francesc Lloret, Miguel Julve|2014|Eur.J.Inorg.Chem.||4564|doi:10.1002/ejic.201402190
CCDC 155167: Experimental Crystal Structure Determination
2002
Related Article: G.Barone, T.G.Hibbert, M.F.Mahon, K.C.Molloy, I.P.Parkin, L.S.Price, I.Silaghi-Dumitrescu|2001|J.Chem.Soc.,Dalton Trans.||3435|doi:10.1039/b010157p
Ligands hybrides : synthèse et chimie de coordination
2011
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 …
Efficient Synthesis of β-Halogeno Protected L-Alanines and Their β-Phosphonium Derivatives.
2003
Abstract Ring opening of oxazolines, prepared from l -serinates, with trimethylsilyl halides (TMSX) led to β-halogeno-N-benzoyl-α-amino esters in good to excellent yields. Quaternization of triphenylphosphine by the β-bromo or -iodo amino esters gave the corresponding β-phosphonium salts in overall yields of up to 93% and with e.e. >96%. Hydrolysis of the ester function afforded the phosphonium salt bearing an N-benzoyl-α-amino acid substituent, with partial racemization. However, the reaction of the TMSX with the carboxylic salt, prepared by saponification of the starting oxazoline ester, furnished the corresponding β-halogeno-N-benzoyl-α-amino acids in 70–95% yields. Quaternization of tri…
Capability study of 1-butyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide and trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phos…
2018
Abstract The liquid-liquid equilibria of the ternary systems water (1) + 1-propanol (2) + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][Tf2N]) (3) and water (1) + 1-propanol (2) + trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate ([TDTHP][Phosph]) (3) at 283.2, 303.2 and 323.2 K and atmospheric pressure were determined to study their behaviour, determine their thermodynamic parameters and know the capability as solvents of [bmim][Tf2N] and [TDTHP][Phosph] in the separation of the azeotropic mixture water + 1-propanol. The non-random two-liquid (NRTL) and universal quasichemical (UNIQUAC) models were used in the calculation of the thermodynamic par…
Use of alkylarsonium directing agents for the synthesis and study of zeolites
2019
[EN] Expanding the previously known family of -onium (ammonium, phosphonium, and sulfonium) organic structure-directing agents (OSDAs) for the synthesis of zeolite MFI, a new member, the arsonium cation, is used for the first time. The new group of tetraalkylarsonium cations has allowed the synthesis of the zeolite ZSM-5 with several different chemical compositions, opening a route for the synthesis of zeolites with a new series of OSDA. Moreover, the use of As replacing N in the OSDA allows the introduction of probe atoms that facilitate the study of these molecules by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (MAS NMR), and X-ray absorption spectroscopy (XAS)…
Streoselective hemisynthesis of heterosubstituted aminoacidsApplication on radiofluorolabeling for peptide imaging.
2017
Stereoselective hemisynthesis of lateral chain heterosubstituted aminoacids.Applications on radiofluorolabeling for peptide imaging.This thesis work, which was carried out at the Institute of Molecular Chemistry of the University of Burgundy and in collaboration with the Institute of Cognitive and Integrative Neurosciences of Aquitaine, focuses on the development of new methods for the synthesis of side chain heterosubstituted amino acids including phosphine containing or silyl groups, as well as on their applications. In a first part, the synthesis of side chain silylated amino acids is achieved without racemization using a key Wittig reaction between a phosphonium salt, derived from L-asp…