Tetraethylammonium cation

Figure 4. Activity coefficients of cations relative to the tetraethylammonium cation in sulphuric acid-water mixtures. A—anilinium ions 1, unsubstituted 2, J5-C1 3, P-NO2 4, m-N02. B—benzamide cation. C—a typical carbonium ion, (p-MeOCgHajsC. A and C, after Boyd, 1963 B, after Sweeting and Yates, 1966.

In Ref 169, some peculiarities associated with adsorption of alkyne peroxides from DM F-water solutions onto the mercury electrode in the presence of tetraethylammonium cations have been described. Polarography and electrocapillary measurements were employed as the experimental techniques. It has been shown that interfacial activity of these peroxides was determined by the species generated as a result of associative interactions between peroxides and DMF and tetraethylammonium cations. 

In the solid state, crystal packing forces should be considered since they can appreciably affect the crystal structure. For example, as previously mentioned, the replacement of the tetraethylammonium cation by the bis(triphenylphos-phine)iminium cation for the [ W2(CO)io(m2-H)] species dramatically changes the solid-state structure of the monoanion. For further insight into the possible influence of packing forces on the nature of the Cr-H-Cr bond in the [Cr2-(CO)io(M2-H)]- monoanion, a neutron diffraction study of the corresponding bis(triphenylphosphine)iminium salt, that has been shown by x-ray diffraction... 

Fig. 15.21. Molecular drawing depicting the size of 18-crown-6, with the tetraethylammonium cation fitting into the central cavity.

Ion radius is given in parentheses, a Decomposition temperature, [Nuu]+, tetramethylammonium cation [N2222]+, tetraethylammonium cation [EMIM]+, l-ethyl-3-methylimidazolium cation. 

Figure 1. Yield of pentasil zeolites (percentage crystallization) as a function of time. Abbreviations are C, for mono-n-butylair ne, CU for mono-n-propylamine, C2 for mono-n-ethylamine, C. for mono-n-methylamine, di-C, for di-n-propylamine, di-C, for di-n-propylamine,+di-C2 for di-n-ethylamine, di-n-C.. for di-n-methylamine, TPA Al-free for the aluminium-free synthesis with the tetrapr pylammonium cation, TPA for tetrapropylammonium cation, TEA Al-free for the+aluminium-free synthesis with the tetraethylammonium cation, TEA for tetraethylammonium cation and tri-C for tri-n-propylamine.

Both thiourea (tu) and thiosemicarbazide (tsc) are bifunctional ligands, containing a DD face in addition to one or two co-ordination sites. The reaction of [Zn(tu)4]2+ with a dicarboxylate normally occurs with displacement of thiourea to give coordination polymers of the type [Zn(tu)2(p-dicarboxylate)] in which the chains are cross-linked by DD-AA interactions [157]. The fumarate derivative contains identical inter-plane hydrogen bonding to that observed in (NEt4)2 [fumarate] 2tu [158], in which the zinc atom has formally been replaced by two tetraethylammonium cations. 

Murayama and Aoki have also revealed the ability of a resorcin[4]arene to assemble with hydroxylated solvent molecules to form an assembly with a structure that conforms to a tetragonal prism. Specifically, two tetraethylresorcin[4]arenes assembled with eight water molecules to give an anionic capsule in the solid state.55 The capsule accommodated a tetraethylammonium cation, which interacted with the inner walls of the host via cation-Tt forces. Similar assemblies involving derivatized resorcin[4]arenes have also been described.56 In particular, the resorcin[4]arene of Aoki et al.56 was also shown to assemble with 10 water molecules to give a capsule that hosted both a triethylammonium cation and a water molecule.57 The encapsulated guests assembled via a N+-H O-hydrogen bond. Shivanyuk et al. have also described the ability of two hydroxylated resorcin[4]arenes to assemble with 16 water molecules to form a capsule that accommodated either four acetonitrile molecules or a quinuclidinium ion.58... 

The synthesis mixtures were crystallized by heating at the crystallization temperature (usually 135-145°C) in PTFE lined stainless steel 60 ml autoclaves. During crystallization the autoclaves are rotated at 60 rpm. After quenching with tap water, the solids are recovered by centrifugation and washed with distillate water until pH <9. Then the solids were dried at 100°C for several hours and calcined at 580°C to remove the tetraethylammonium cations occluded into the zeolitic channels. 

In complex 2.14 [41f, the thiourea molecules and acetate ions build a three-dimensional host lattice in a 4 1 ratio, generating two channel systems that are arranged alternately along the [110] and [TlO] directions, as shown in Figures 22 and 23, respectively. The tetraethylammonium cations are accommodated in a single column within each channel. The thiourea-anion lattice comprises zigzag ribbons running parallel to the [110] and [TlO] directions, and parallel undulate... 

The synthesis and characterization of the intermediate-silica zeolite ZSM-25 in the presence of sodium and tetraethylammonium cations is described. The overall characterization results of this study suggest that ZSM-25 is probably an 8-ring or constrained 10-ring pore material containing 4-rings as the smallest structural unit. However, the proton form of ZSM-25 was found to have a poor thermal stability, revealing a serious drawback in its applications as a shape-selective catalyst for acid-catalyzed hydrocarbon conversions. 

Ni, J.X. XJ Nuclear magnetic relaxation of tetraethylammonium cation in poly(acrylic acid) solution. NewJ. Chem. 1999, 23 (11), 1071-1073. 

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