Beryllium carbonate bonding

The organometallic compound chemistry of the 2A metals is similar to that of the 1A metals, and ionically bonded compounds predominate. As is the case with lithium in group 1 A, the first 2A element, beryllium, behaves atypically, with a greater covalent character in its metal-carbon bonds. 

Only one bimetallic mechanism is presented here, as an example, the one originally proposed by Natta. He felt that chemisorptions of the organometallic compounds to transition metal halides take place during the reactions. Partially reduced forms of the di- and tri-chlorides of strongly electropositive metals with a small ionic radius (aluminum, beryllium, or magnesium) facilitate this. These chemisorptions result in formations of electron-deficient complexes between the two metals. Such complexes contain alkyl bridges similar to those present in dimeric aluminum and beryllium alkyls. The polymeric growth takes place from the aluminum-carbon bond of the bimetallic electron-deficient complexes . ... 

The beryllium-carbon double bond lengths and bond energy in H2C=Be(CO)2 were calculated to be 1.592 A and 99.6 kcal mol respectively. The synthesis, structure and reactivity have been reported of MeBe[Ti -HB(3-Bu -pz)3] obtained from Me2Be and Tl[Ti -HB(3-Bu -pz)3]. This reacts with H2S or I2 to give Be-Me bond cleavage. 

As was the case for beryllium, a digonal carbon atom suggests that the localized hybridization is sp. Unlike beryllium [(E )(2s )] discussed in (I) above, carbon [(Is ) (25 )(2p )] will have two electrons, one each in each localized 2p orbital even after hybridization has been effected. Using the two localized sp hybrid orbitals on each carbon (which will form stronger bonds than those that might be made by an overlap of other localized available orbitals), three carbon-carbon bond and two carbon-hydrogen bonds. There are two localized 2p orbitals on each carbon available to form two, mutually orthogonal it bonds by sidewise overlap. 

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. ... 

Diamondlike Carbides. SiUcon and boron carbides form diamondlike carbides beryllium carbide, having a high degree of hardness, can also be iacluded. These materials have electrical resistivity ia the range of semiconductors (qv), and the bonding is largely covalent. Diamond itself may be considered a carbide of carbon because of its chemical stmeture, although its conductivity is low. 

Notice that the beryllium atom has no unpaired electrons, the boron atom has one, and the carbon atom two. Simple valence bond theory would predict that Be, like He, should not form covalent bonds. A boron atom should form one bond, carbon two. Experience tells us that these predictions are wrong. Beryllium forms two bonds in BeF2 boron forms three bonds in BF3. Carbon ordinarily forms four bonds, not two. 

The beryllium atom, like boron and carbon, can promote an electron in order to form more chemical bonds ... 

We have considered solid forms of the elements fluorine, oxygen, nitrogen, and carbon. In each case, a solid is formed in which the bonding capacity is completely satisfied. The remaining elements of the second row. that is, beryllium,... 

Formally, the lone pairs on molecular nitrogen, hydrogen cyanide, and carbon monoxide are sp hybrid orbitals, whereas NLMO hybridizations calculated even lower p contributions. Hence, these lone pairs have low directionality, the electron density remains close to the coordinating atom and interaction between the lone pair and the Be2+ is comparatively weak. The Be-L bonds are easily disrupted and ligand exchange consequently can proceed with a low activation barrier. A high degree of p character, on the other hand, means that the lone pair is directed toward beryllium, with electron density close to the metal center, and thus well suited for coordination. 

The problem of the stability of the complexes of the transition metals was for many years a puzzling one. Why is the cyanide group so facile in the formation of complexes with these elements, whereas the carbon atom in other groups, such as the methyl group, does not form bonds with them Why do the transition metals and not other metals (beryllium, aluminum, etc.) form cyanide complexes In the ferro-... 

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