Search results for "ether"
showing 10 items of 986 documents
Reinvestigation of the Pd-catalysed bis(silylation) of alkynes with 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane: Unexpected formation of th…
2013
International audience; The bis(silylated) alkenes Z-(PhSCH2)Me2SiC(H)=C(Fc)SiMe2(CH2SPh) (2) and Z-(PhSCH2)Me2SiC(H)=C(bipheny)SiMe2(CH2SPh) (3) have been prepared by Pd-catalysed double silylation of ethynylferrocene and 4-ethynyl-1,1'-biphenyl in the presence of 1,1,2,2-tetramethyl-1,2-bis(phenylthiomethyl)disilane (1). A reinvestigation on the interaction of 1 with [PdCl2(PhCN)2] in technical-grade CH2Cl2 as solvent revealed competition between reduction to elemental palladium (due to oxidative addition of the Si-Si bond across Pd(II) and subsequent reductive elimination) and formation of an unusual eight-membered chelate complex cis-[PdCl2{(PhSCH2SiMe2)2O}] (4), which is fluxional in s…
Three 2,5-dialkoxy-1,4-diethynylbenzene derivatives
2008
2,5-Diethoxy-1,4-bis[(trimethylsilyl)ethynyl]benzene, C20H30O2Si2, (I), constitutes one of the first structurally characterized examples of a family of compounds, viz. the 2,5-dialkoxy-1,4-bis[(trimethylsilyl)ethynyl]benzene derivatives, used in the preparation of oligo(phenyleneethynylene)s via Pd/Cu-catalysed cross-coupling. 2,5-Diethoxy-1,4-diethynylbenzene, C14H14O2, (II), results from protodesilylation of (I). 1,4-Diethynyl-2,5-bis(heptyloxy)benzene, C24H34O2, (III), is a long alkyloxy chain analogue of (II). The molecules of compounds (I)–(III) are located on sites with crystallographic inversion symmetry. The large substituents either in the alkynyl group or in the benz…
A statistical design of experiments for optimizing the MALDI-TOF-MS sample preparation of polymers. An application in the assessment of the thermo-me…
2011
[EN] The sample preparation procedure for MALDI-TOF MS of polymers is addressed in this study by the application of a statistical Design of Experiments (DoE). Industrial poly (ethylene terephthalate) (PET) was chosen as model polymer. Different experimental settings (levels) for matrixes, analyte/matrix proportions and concentrations of cationization agent were considered. The quality parameters used for the analysis were signal-to-noise ratio and resolution. A closer inspection of the statistical results provided the study not only with the best combination of factors for the MALDI sample preparation, but also with a better understanding of the influence of the different factors, individua…
UCST-type behavior of poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA) in aliphatic alcohols: solvent, co-solvent, molecular weight, a…
2011
Poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA) is shown to possess insoluble–soluble transitions (UCST-type phase behavior) in a large variety of aliphatic alcohols. Samples of different molecular weights ranging from 5 kg mol−1 to 23 kg mol−1 prepared by the RAFT process and featuring different end groups at each end were analyzed by cloud point measurements. Transitions occurred sharply and were fully reversible. The UCST was found to increase with an increasing molecular weight. Hydrophobic (alkyl chain) end groups were found to lower the critical temperature in isopropanol, while rigid aromatic end groups raised the transition temperature. In ternary mixtures of isoprop…
CCDC 1422372: Experimental Crystal Structure Determination
2016
Related Article: Sarah Keller, Antonio Pertegás, Giulia Longo, Laura Martínez, Jesús Cerdá, José M. Junquera-Hernández, Alessandro Prescimone, Edwin C. Constable, Catherine E. Housecroft, Enrique Ortí, Henk J. Bolink|2016|J.Mater.Chem.C|4|3857|doi:10.1039/C5TC03725E
CCDC 2081394: Experimental Crystal Structure Determination
2021
Related Article: Marco Meyer, Lorenzo Mardegan, Daniel Tordera, Alessandro Prescimone, Michele Sessolo, Henk J. Bolink, Edwin C. Constable, Catherine E. Housecroft|2021|Dalton Trans.|50|17920|doi:10.1039/D1DT03239A
CCDC 1581155: Experimental Crystal Structure Determination
2018
Related Article: Sarah Keller, Fabian Brunner, José M. Junquera‐Hernández, Antonio Pertegás, Maria‐Grazia La‐Placa, Alessandro Prescimone, Edwin C. Constable, Henk J. Bolink, Enrique Ortí, Catherine E. Housecroft|2018|ChemPlusChem|83|217|doi:10.1002/cplu.201700501
CCDC 802648: Experimental Crystal Structure Determination
2011
Related Article: R.D.Costa, D.Tordera, E.Orti, H.J.Bolink, J.Schonle, S.Graber, C.E.Housecroft, E.C.Constable, J.A.Zampese|2011|J.Mater.Chem.|21|16108|doi:10.1039/c1jm12607e
CCDC 974020: Experimental Crystal Structure Determination
2014
Related Article: Edwin C. Constable, Catherine E. Housecroft, Gabriel E. Schneider, Jennifer A. Zampese, Henk J. Bolink, Antonio Pertegás, Cristina Roldan-Carmona|2014|Dalton Trans.|43|4653|doi:10.1039/C3DT53477D
CCDC 1848218: Experimental Crystal Structure Determination
2019
Related Article: Abdou K. D. Dimé, Hélène Cattey, Dominique Lucas, Charles H. Devillers|2018|Eur.J.Org.Chem.|2018|4834|doi:10.1002/ejic.201801142