Cations beryllium

Fig. 1 Absorption scanning curve of the alizarin complexes of barium (1), strontium (2), calcium (3), magnesium (4) and beryllium cations (5). The amounts appUed were 2 pg in each case.

Benztriazole, derivatives 281 ff 2-(2-Hydroxy-5-niethylphenyl)- 282 2-(2-Hydroxy-3-(l -methylpropyl)-5-tert-butylphenyl- 283 Berberine reagent 44,213 Beryllium cations 144,145,311,312 Besthorn s hydrazone reagent 347 Beta-blockers 74, 299, 301, 426—428 Beta-fronts 126 Beta-radiation 12 Betulae, Extr. 279 Betulic acid 59... 

With aliphatic amines, the decomposition catalysis is moderate with heterocyclic aromatic amines (pyridine, quinoline), 0.1 % of amine is sufficient to cause maleic anhydride to decompose. An accident has also been mentioned with NaOH. This decomposition also takes place in the presence of sodium, lithium, ammonium, potassium, calcium, barium, magnesium and beryllium cations. 

Beside four-coordinate Be2+ structures, a couple of five-coordinate structures are known, e.g., Dehnicke s [BeCl(12-crown-4)]+ (179). The combination of beryllium cations and different crown ethers is of particular interest, not only because the Nobel Prize was awarded in part for the development of crown ethers (15), but also because crown ethers are common building blocks in all kinds of chemistry (180,181), with a wide range of applications. Since Be2+ is the smallest metal ion, the binding modes of Be2+ and crown ethers can lead to unexpected structural motifs. 

One of the surprising aspects of this and other studies using naked metal ions as models for electron-transfer catalysis are the many analogies found to known transition metal chemistry, either in the gas phase with naked ions or for complexes under more normal conditions. Clearly, such simple models as the beryllium cation cannot account for transition metal reactivity, but they do have the advantage that, because of their very simplicity, the reasons for their effects are relatively clear. The fact that Be can catalyze a given reaction does not necessarily mean that, for instance, a transition metal does not use d-orbitals to catalyze the same reaction but it does mean that d-orbitals are not a prerequi-... 

Be +, also known as the beryllium cation. By losing two electrons, beryllium, which is in Group llA, assumes a full octet valence shell, with two electrons like helium. 

Delpuech et al. (106) examined the tetrahedral solvates of the beryllium cation with trimethyl phosphate (TMPA), dimethyl methyl phosphonate (DMMP), N,iV-dimethylamido-0,0 -dimethyl phosphate (DMADM P), bis-A,iV-dimethylamido-0-methyl phosphate (TMDAMP), and hexamethylphosphorotriamide (HMPT) by NMR including that of Be. The kinetics of ligand exchange ... 

Solution As seen in Table 1.3, beryllium (Be) has two valence electrons. To achieve the filled-shell electron arrangement of helium, it must lose both of its valence electrons. Thus, the beryllium cation will carry two positive charges and is represented by Be. ... 

The beryllium cation in aqueous solution is surrounded by four water molecules, whereas the corresponding heavier cations are surrounded by six.That is, Be ( y) is more likely [Be(H20)4], whereas its congeners are [M(H20)5]. Speculate on a reason for this difference. 

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