Metallorganische Verbindungen von einwertigen Elementen der 13. Gruppe: schwache Assoziation an monomere, vielseitige Zweielektronen-Donoren

Abstract

Schwach assoziiert ist Strukturuntersuchungen zufolge das hexamere [GaCp*] (Cp* = C5Me5) im Kristall (siehe Bild). Dies wirft auch bei den monomeren InI‐ und TlI‐Verbindungen [M(2,4,6‐Trip3C6H2)] (M = In, Tl; Trip = 2,4,6‐iPr3C6H2) ein neues Licht auf die bei einwertigen Elementen der 13. Gruppe auftretende Assoziation und Aggregation im Festkörper, die vom Liganden abhängen. Mit der Synthese von [Ni0{In[C(SiMe3)3]}4], einem Komplex mit endständig gebundenen InIR‐Liganden, bieten sich Alternativen für σ‐Donor/π‐Acceptor‐Liganden in der metallorganischen Chemie an. Die jüngsten Entwicklungen auf diesem Gebiet lassen neue und faszinierende Möglichkeiten für die Herstellung von Hauptgruppenelement‐Übergangsmetall‐Clustern erwarten.

Oxidative Addition of Group 13 and 14 Metal Halides and Alkyls to Ga(DDP) (DDP = Bulky Bisimidinate)

“…The chemistry of monovalent group 13 compounds ER is a fascinating part of modern inorganic chemistry and has been explored extensively in the past 20 years. – Their coordination chemistry to electron-rich transition metals is very rich, especially for R = Cp*, ranging from classical organometallic reactions such as C−H or C−C bond activation reactions, – to unprecedented product classes, for example, homoleptic cluster compounds of the type M a (ER) b . – Quite recently, Power, Roesky, and Hill added a new class of compounds to the series ER, that is the bulky bisimidinates E(DDP) (DDP = 2-{(2,6-diisopropyl-phenyl)amino}−4-{(2,6-diisopropylphenyl)imino}−2-pentene). – Additionally, the related borylene complex [B{ArNCH} 2 ]Li was reported by Segawa et al in 2006 . The chemistry of these compounds has proven to be very prosperous and especially in the case of Al(DDP) a variety of coordination, oxidation and insertion reactions were studied in some detail. – Thus, the aluminum center in Al(DDP) has been shown to be rather Lewis acidic, coordinating also weak donors such as the aromatic C−F group of a B(C 6 F 5 ) 3 moiety .…”

Insertion of the Ga(I) Bis-imidinate Ga(DDP) into the Metal Halogen Bonds of Rh(I) Complexes. How Electrophilic Are Coordinated Ga(DDP) Fragments?

“…Low-valent group 13 element organyls of the general type ECp* (E = Al, Ga) have been widely used as ligands for various transition metal centers. − Their σ-donor capability is rather strong, leading to a Lewis acidic group 13 metal coordinated to an electron-rich transition metal in the complexes. , These intermetallic compounds have been shown to undergo classical organometallic reactions such as C−H, Si−H, or C−C bond activations in which the group 13 metal usually plays a crucial role being not only a spectator ligand but actively taking part as a reaction partner. , Thus, GaCp* readily inserts into the metal−halogen bonds of [RhCp*Cl 2 ] 2 and [Rh( p -cymene)Cl 2 ] 2 forming cagelike complexes with terminal Ga−Cl bonds and Ga−Cl−Ga bridges. − Furthermore, a C−C bond rupture process is taking place in the reaction of RhCp*(L)(CH 3 ) 2 with GaCp* giving the zwitterion RhCp*(C 5 Me 4 GaMe 3 ). The C−C bond activation was shown to topologically take place at the gallium instead of the rhodium center. , In the course of these reactivity studies of reactive transition metal fragments with E I R compounds we became interested in sterically more encumbered ligands to stabilize coordinatively unsaturated transition metal centers.…”