Well-Defined, Solvent-Free Cationic Barium Complexes: Synthetic Strategies and Catalytic Activity in the Ring-Opening Polymerization of Lactide
In: Inorganica Chimica Acta Inorganica Chimica Acta, 2012, 380, pp.2-13. ⟨10.1016/j.ica.2011.09.020⟩ Inorganica Chimica Acta, Elsevier, 2012, 380, pp.2-13. ⟨10.1016/j.ica.2011.09.020⟩; (2012-01-15)
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Zugriff:
International audience; Well-defined, solvent-free cationic barium complexes of the type [{LnX}Ba]+*[H2N{B(C6F5)3}2]− stabilized by multidentate amino-ether phenoxide or fluorinated amino-ether alkoxide ligands {LnX}− are available according to original, general and high-yield protocols. These cations have been prepared by (i) hydrolysis of heteroleptic complexes {LnX}BaN(SiMe2H)2 stabilized by Ba***H−Si interactions with [H(OEt2)2]+*[H2N{B(C6F5)3}2]−, or (ii) reaction of {Ba[N(SiMe2H)2]2}n with the doubly acidic pro-ligands [{LnX}HH]+*[H2N{B(C6F5)3}2]−. The solid-state structures of [{LO2}Ba(THF)2]+*[H2N{B(C6F5)3}2]− ({LO2}H = 2-[(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)methyl]-4,6-di-tert-butylphenol) and [{RO2}Ba]+*[H2N{B(C6F5)3}2]− {RO2}H = 2-[(1,4,7,10-tetraoxa-13-azacyclopentadecan-13-yl)methyl]-1,1,1,3,3,3-hexafluoropropan-2-ol) are described, highlighting the key role of internal secondary Ba***F−C interactions in these highly electrophilic species. In combination with an excess of an external nucleophile (chosen from benzyl alcohol, 1,3-propanediol, benzyl amine or an hydroxyl-functionalized alkoxy-amine) as a co-initiator, some of these Ba cations provide extremely efficient catalysts for the immortal ring-opening polymerization of l-lactide in the temperature range 0-30 °C, converting rapidly up to 5000 equiv. of monomer in a controlled fashion and with excellent end-group fidelity.
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Well-Defined, Solvent-Free Cationic Barium Complexes: Synthetic Strategies and Catalytic Activity in the Ring-Opening Polymerization of Lactide
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Autor/in / Beteiligte Person: | Liu, Bo ; Roisnel, Thierry ; Sarazin, Yann ; Institut des Sciences Chimiques de Rennes (ISCR) ; Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes) ; Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) ; Université de Rennes 1 (UR1) ; Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes) ; Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) |
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Quelle: | Inorganica Chimica Acta Inorganica Chimica Acta, 2012, 380, pp.2-13. ⟨10.1016/j.ica.2011.09.020⟩ Inorganica Chimica Acta, Elsevier, 2012, 380, pp.2-13. ⟨10.1016/j.ica.2011.09.020⟩; (2012-01-15) |
Veröffentlichung: | HAL CCSD, 2012 |
Medientyp: | unknown |
ISSN: | 0020-1693 (print) |
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