NHC-Stabilised Parent Tripentelyltrielanes.

A missing family of the extremely air sensitive tripentelyltrielanes was discovered. Their stabilisation was achieved by using the bulky NHC IDipp (NHC=N-heterocyclic carbene, IDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene). The tripentelylgallanes and tripentelylalanes IDipp ⋅ Ga(PH ) (1 a), IDipp ⋅ Ga(AsH ) (1 b), IDipp ⋅ Al(PH ) (2 a) and IDipp ⋅ Al(AsH ) (2 b) were synthesised by salt metathesis of IDipp ⋅ ECl (E=Al, Ga, In) with alkali metal pnictogenides such as NaPH /LiPH  ⋅ DME and KAsH , respectively.

NHC-stabilized Parent Arsanylalanes and -gallanes.

The synthesis and characterization of the unprecedented compounds IDipp⋅E'H AsH (E'=Al, Ga; IDipp=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) are reported, the first monomeric, parent representatives of an arsanylalane and arsanylgallane, respectively, stabilized only by a LB (LB=Lewis Base). They are prepared by a salt metathesis reaction of KAsH with IDipp⋅E'H Cl (E'=Al, Ga). The H -elimination pathway through the reaction of AsH with IDipp⋅E'H (E'=Al, Ga) was found to be a possible synthetic route with some disadvantages compared to the salt metathesis reaction.

Phosphanylalanes and Phosphanylgallanes Stabilized only by a Lewis Base.

The synthesis and characterization of the first parent phosphanylalane and phosphanylgallane stabilized only by a Lewis base (LB) are reported. The corresponding substituted compounds, such as IDipp⋅GaH PCy (1) (IDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene) were obtained by the reaction of LiPCy with IDipp⋅GaH Cl. However, the LB-stabilized parent compounds IDipp⋅GaH PH (3) and IDipp⋅AlH PH (4) were prepared via a salt metathesis of LiPH ⋅DME with IDipp⋅E'H Cl (E'=Ga, Al) or by H -elimination reactions of IDipp⋅E'H (E'=Ga, Al) and PH , respectively.