Titre :	New strained diphosphoniums and their corresponding bis-ylides : preparation, characterization and stability
Type de document :	texte imprimé
Auteurs :	Mohammed Abdalilah, Auteur ; Remi Chauvin, Directeur de thèse
Langues :	Anglais (eng)
Tags :	CARBON LIGANDS  DIPHOSPHONIUM YLIDES  DIAMINOCARBENES  ELECTROSTATIC INTERACTION  CYCLOADDITION REACTION  COMPLEXATION
Résumé :	"The introduction chapter presents the general context of this manuscript which is mainly focused on neutral eta1-carbon ligands potentially available for catalytic applications. Three types of neutral eta1-representatives satisfying the octet role for the carbon atom in the free state, and depending on the hybridization state of the coordinating carbon atom are thus distinguished: the ylide-type ligands (sp3), the carbenes (sp2) and the cumulenylidenes (sp). The second chapter of this study describes the preparation and the characterization of a series of highly strained vicinal cyclic/acyclic diphosphoniums derived from 1,2- bis(diphenylphosphino)benzene. Their formal electrostatic and possible van der waals strains are then discussed through P+....+P distances in their crystalline state. In the third chapter and after a brief introduction about the typology of molecules containing two phosphonium ylide moities, a synthetic strategy explains two distinct methods to prepare cyclic/acyclic bis-ylides. The first method applies the classical route which consists of deprotonation of the diphsophonium precursors, while a more original route based on the coupling of 1,2-bis(diphenylphosphino)benzene and different electron-poor alkynes through a direct cycloaddition cyclization reaction is then presented. Due to the relative stability of the bis-ylides obtained by the cycloaddition reaction, the protonation reaction -mono and di- allowed us to isolate diphosphoniums which could not be obtained by the classical method. Interestingly, a highly reactive cyclic bis-ylide has been obtained by the classical method, trapped by rhodium(1) complex and fully characterized. In summary, all the results reported in this thesis highlight that the use of extremely electronrich carbon ligands namely diphosphonium ylides might represent an interesting alternative to the classical phosphorus congeners in homogeneous catalysis which deserves more attention."
Document :	Thèse de Doctorat
Etablissement_delivrance :	Université Toulouse 3
Date_soutenance :	29/04/2010
Ecole_doctorale :	Sciences de la matière (SdM)
Domaine :	Chimie organométallique et de coordination
En ligne :	http://thesesups.ups-tlse.fr/888/

New strained diphosphoniums and their corresponding bis-ylides : preparation, characterization and stability [texte imprimé] / Mohammed Abdalilah, Auteur ; Remi Chauvin, Directeur de thèse . - [s.d.].
Langues : Anglais (eng)

Tags :	CARBON LIGANDS  DIPHOSPHONIUM YLIDES  DIAMINOCARBENES  ELECTROSTATIC INTERACTION  CYCLOADDITION REACTION  COMPLEXATION
Résumé :	"The introduction chapter presents the general context of this manuscript which is mainly focused on neutral eta1-carbon ligands potentially available for catalytic applications. Three types of neutral eta1-representatives satisfying the octet role for the carbon atom in the free state, and depending on the hybridization state of the coordinating carbon atom are thus distinguished: the ylide-type ligands (sp3), the carbenes (sp2) and the cumulenylidenes (sp). The second chapter of this study describes the preparation and the characterization of a series of highly strained vicinal cyclic/acyclic diphosphoniums derived from 1,2- bis(diphenylphosphino)benzene. Their formal electrostatic and possible van der waals strains are then discussed through P+....+P distances in their crystalline state. In the third chapter and after a brief introduction about the typology of molecules containing two phosphonium ylide moities, a synthetic strategy explains two distinct methods to prepare cyclic/acyclic bis-ylides. The first method applies the classical route which consists of deprotonation of the diphsophonium precursors, while a more original route based on the coupling of 1,2-bis(diphenylphosphino)benzene and different electron-poor alkynes through a direct cycloaddition cyclization reaction is then presented. Due to the relative stability of the bis-ylides obtained by the cycloaddition reaction, the protonation reaction -mono and di- allowed us to isolate diphosphoniums which could not be obtained by the classical method. Interestingly, a highly reactive cyclic bis-ylide has been obtained by the classical method, trapped by rhodium(1) complex and fully characterized. In summary, all the results reported in this thesis highlight that the use of extremely electronrich carbon ligands namely diphosphonium ylides might represent an interesting alternative to the classical phosphorus congeners in homogeneous catalysis which deserves more attention."
Document :	Thèse de Doctorat
Etablissement_delivrance :	Université Toulouse 3
Date_soutenance :	29/04/2010
Ecole_doctorale :	Sciences de la matière (SdM)
Domaine :	Chimie organométallique et de coordination
En ligne :	http://thesesups.ups-tlse.fr/888/