Beryllium dichloride

Nucleophilic carbene 4 (R = Me, R = H) has been shown to disrupt the polymeric structure of beryllium dichloride to form an ionic carbene complex, 10 (15). The crystal structure of 10 revealed that the cation possesses a distorted tetrahedral coordination geometry at the beryllium center. The average Be-Cl bond distance (2.083(7) A) is... 

Common synthetic routes to beryllium amides, which were summarized in Ref. 1, involve the direct or indirect amination of beryllium hydride, beryllium chloride, a beryllium alkyl or amide precursor. Beryllium amides with bulky substituents are generally synthesized via the trans-metallation of beryllium dichloride with the lithium amides. The reaction of beryllium dichloride with secondary amines in the presence of an alkyllithium represents a less common synthetic route to beryllium amides. The formation ofbery Ilium amides via the reaction of an alkyl beryllium as well as beryllium hydride species with amines is also known. ... 

A screw axis brings the infinite rod into coincidence with itself after a translation through a distance t accompanied by a rotation through an angle a. The screw axis is of the order n = 360°/a. It is a special case when n is an integer. The iron chain and the beryllium dichloride chain have a fourfold (or fourth-order) screw axis, 42. Their overall symmetry is (a) m 42 m. For the screw axis of the second order, the direction of the rotation is immaterial. Other screw axes may be either... 

Figure 8-10. Rods with 42 screw-axis, (a) Iron-chain in the vicinity of the Royal Palace in Madrid (photograph by the authors) (b) Beryllium dichloride chain in the crystal.

They will be orthogonal to each other, and also to the two sp hybrid orbitals. If two atoms were hybridised into the sp configuration, then the remaining p orbitals could be empty as in beryllium dichloride, BeCl2 or alternatively, they could form two 7t bonds, each orthogonal to the other, but... 

BERYLLIUM DICHLORIDE (7787-47-5) Water contact produces heat and hydrochloric acid. Attacks metals in the presence of moisture. 

Beryllium complexes, 3 amines, 7 anionic, 10 hydrates, 6 phthalocyanine, 59 poly carboxylic acid, 33 Schiff bases, 28 Beryllium dichloride ether complexes, 8 Beryllium difluoride ammine complexes, 7 Beryllium dihalides sulfide complexes, 10 Beryllium halides amine complexes, 8 ammonia complexes, 7 carbonyl complexes, 9 Beryllium nitrate basic, 32... 

Real objects are not infinite. For symmetry considerations, it may be convenient to look only at some portions of the whole, where the ends are not yet in sight, and extend them in thought to infinity. A portion of an iron chain and a chain of beryllium dichloride in the crystal are shown in Figure 8-10. Translation from unit to unit is accompanied by a 90° rotation around the translation axis. A portion of a spiral stairway displaying screw-axis symmetry is shown in Figure 8-lla. The imaginary impossible stairway of Figure 8-llb indeed seems to go on forever. 

A new complex formed between endo-dicyclopentadiene and gold(I) chloride has been prepared by a substitution reaction in dichloromethane, whereby carbon monoxide in dissolved [AuCl(CO)] has been displaced by the endo-dicyclopentadiene ligand/-The first example of the use of the Hofmann/Fischer reagent cyclopentadienylindium(I) for carbon-carbon bond formation and the demonstration of a one-pot tandem addition/intramolecular Diels Alder reaction in aqueous media have been reported/ The synthesis and solid-state structures of two new beryllocenes have been reported. These are [Be(CsMe4H)2] and [Be(C5Mes)2], which are obtained in the metathesis reactions of the potassium salts of the cyclopentadienes with beryllium dichloride, the former at room temperature and the latter at elevated (115 °C) temperature. ... 

Lewis noted that fused beryllium dichloride has a very low electrical conductivity and suggested that the Be-Cl bonds are covalent rather than ionic. This implies that the Be atom has only two electron pairs in the valence shell. 

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