Aluminium Diphosphamethanides: Hidden Frustrated Lewis Pairs.
The synthesis and characterisation of two aluminium diphosphamethanide complexes, [Al(tBu)2 {κ(2) P,P'-Mes*PCHPMes*}] (3) and [Al(C6 F5 )2 {κ(2) P,P'-Mes*PCHPMes*}] (4), and the silylated analogue, Mes*PCHP(SiMe3 )Mes* (5), are reported. The aluminium complexes feature four-membered PCPAl core structures consisting of diphosphaallyl ligands. The silylated phosphine 5 was found to be a valuable precursor for the synthesis of 4 as it cleanly reacts with the diaryl aluminium chloride [(C6 F5 )2 AlCl]2 . The aluminium complex 3 reacts with molecular dihydrogen at room temperature under formation of the acyclic σ(2) λ(3) ,σ(3) λ(3) -diphosphine Mes*PCHP(H)Mes* and the corresponding dialkyl aluminium hydride [tBu2 AlH]3 . Thus, 3 belongs to the family of so-called hidden frustrated Lewis pairs.
Institute of Inorganic Chemistry, Division Molecular Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany.
Steffen
S
Styra
Institute of Inorganic Chemistry, Division Molecular Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany.
Michael
M
Radius
Institute of Inorganic Chemistry, Division Molecular Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany.
Eric
E
Moos
Institute of Physical Chemistry, Division Theoretical Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 2, 76131, Karlsruhe, Germany.
Angela
A
Bihlmeier
Institute of Inorganic Chemistry, Division Molecular Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, 76131, Karlsruhe, Germany. breher@kit.edu.
Frank
F
Breher
aluminium; frustrated Lewis pairs; hydrogen; phosphorus