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Six new molecular GaCl3 adducts of electron rich compounds of the carbone (carbodiphosphorane, tetraaminoallene) and cyclic alkyl amino carbene (CAAC) families have been synthesized and characterized by X-ray crystallography. The sum of their Cl-Ga-Cl angles has been compared to those of 20 other complexes exhibiting various oxygen-, nitrogen-, phosphorus-, and carbon-donor ligands for which good quality X-ray analyses have been reported. The pyramidalization of the GaCl3 moiety in L·GaCl3 complexes has been checked against the computed antisymmetric stretching of the Ga-Cl bonds. It has also been compared to the symmetric stretching of the C-O bonds of the corresponding L·Ni(CO)3 complexes (Tolman Electronic Parameter). On this basis, a relationship between the pyramidalization observed in the gallium complexes and the electronic ligand properties has been established.

Ga‐neration X: Well‐defined neutral and cationic gallium(III) halide complexes have been synthesized and evaluated in catalysis. Both the (NHC)GaX3/AgSbF6 catalytic mixture and isolated (NHC)GaX2+ species function as exquisite π‐Lewis acids in typical GaX3‐catalyzed reactions (see scheme). The cationic complexes are more active than GaX3 and yet more resistant to hydrolysis, which allows lower catalytic loadings and faster reactions.

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SUMMARYThe majority of work in numerical analyses of sheet metal forming operations is based on the simple membrane-shell theory which neglects the effect of sheet bending. While useful information can be extracted from these analyser, especially for stretch-dominated operations, the membrane theory is basically inadequate for analysing the draw-type operations where sheet metal bends, slides and unbends over a draw radius. This paper presents axisymmetric and plane-strain finite element analyses of stretch/draw of sheet metal over a die corner radius. Numerical solutions obtained from a total Lagrangian formulation of a finite-strain thin shell theory are used to indicate the relative significance of including the bending effects in various simple forming operations. Comparisons of the calculated results with available experimental data are also given.

Fluorine-bridged NHC−gallium(III) complexes of the type IPr•GaCl 2 (μ-F)EF n − 1 [IPr = 1,3-bis(2,6diisopropylphenyl)imidazol-2-ylidene, and EF n = SbF 6 or BF 4 ] have been synthesized and characterized in solution and in the solid state. The [BF 4 ] − adduct readily decomposes into gallium fluorides of the type [IPr•GaCl m F 3−m ] (m = 0, 1, or 2) with release of gaseous BF 3 . These results corroborate the trend observed in IPr•GaCl 3 /AgEF n -catalyzed reactions in which a strong anion effect exists.

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