The crystal and molecular structure of trichlorotrimethylaminealuminum(III)

Abstract

1"he crystal and molecular structure of trichlorotrimethylaminealuminum(III) [A1CI3.N(CH3)3] has been determined by a three-dimensional X-ray analysis and is shown to be monomeric. The crystals are monoclinic with a --6.81 +_ 0.02, b = 10.66 _+ 0.03, c = 7.31 +_ 0.02/~; p--118°0 , _+ 5'; space group P21 with Z= 2. The aluminum-nitrogen distance is 1.96/~.

The correlation of dative bond length and parameter n in adducts Me3N—AlMe3-nCln (n ≤ 3)

“…The chlorides 2±4 form, by contrast, an isostructural group (space group P2 1 /m with two formula units per unit cell). Although space group P2 1 has been reported for 4 in an earlier study [5] our data did not give indication of noncentrosymmetry. Both types of structures in this paper are closely related having similar packing of their molecules along the respective b and c axes.…”

“…Assuming this interpretation is true, the same effect could be expected in structure 4 which is isostructural with Me 3 NBCl 3 [11]. The corresponding N± ±Al distance in gas phase, 1.945(35) # e [5], however, coincides with our observations (1.949 # e).…”

“…The intensity statistics for 4 indicate a centrosymmetric structure and the refinement in P2 1 /m proceeded without problems. An alternative refinement in P2 1 as reported by Grant et al [5] leads to additional inversion symmetry, unusual correlation parameters, and the absolute structure parameter could not be refined properly. From this we conclude that P2 1 /m is the correct space group for 4.…”

A General Synthetic Pathway to Lewis Base-Stabilized, MonomericGroup 13/15 Compounds

“…[15] However, compounds containing stronger Lewis acids [e.g. Cl 3 AlϪNMe 3 : 196(1) pm (single-crystal analysis) [16] ; 194.5(35) pm (electron diffraction) [17] ] show comparable AlϪN distances. Compared to analogous Lewis base-stabilized monomers of the type Me 3 NǞAl(R 2 )ERЈ 2 , the dmap adducts show the shortest AlϪN distances [AlϪN (in pm): (7); [6] Me 3 NǞAl(H 2 )PMes 2 200.9(8) [7] ].…”

Synthesis, Reactivity, and Computational Analysis of Halophosphines Supported by Dianionic Guanidinate Ligands

“…The solid-state structure of 6Al ( Figure 3f, Table 2) confirmed the atom connectivity of N(3) to Al(1) with a bond length of 1.936(3) Å, which is in the typical range found for other AlCl3 adducts. 89,90 Compared to 1PCl, 6Al has shortened C( The most notable structural change of 1PCl upon reaction with Cp2Co to form 9 ( Figure 4a, Table 2) is the change in the coordination mode of the guanidinate ligand from  2 -N,N chelating to -N,N bridging. The guanidinate ligand 1 retains its dianionic nature in the bridging mode, as indicated by the carbon-nitrogen bond lengths.…”