Metal-alkyl compounds

In addition, macrocycles have been used to chelate alkyl metal compounds efficiently. Methyltetraphenylporphinatoindium contains an indium atom that is coordinated by the four nitrogen atoms of the porphyrin and has a fifth methyl ligand (57). 

ALKYL-METAL COMPOUNDS STUDIED BY PROTON MAGNETIC RESONANCE SPECTROSCOPY (PMR)... 

ACTIVATION ENERGIES (kcal.mole-1) FOR THE INVERSION OF SOME PRIMARY ALKYL-METAL COMPOUNDS, STUDIED BY PMR... 

Substitution of alkyl-metal compounds by metal salts... 

Reaction between a reducing alkyl metal compound and a transition metal compound proceeds through a series of alkylated transition metal compounds which can decompose into lower valent transition metal compounds and free radicals (284, 289, 318—332). 

Twenty years after Frankland s initial paper, the chemistry of the alkyl-metal compounds had developed to such an extent that Mendeleev could use them in his formulation of the periodic law 176). He made the... 

Alkyl-metallic compounds. Here the alkyl is bound to the metal, e.g.,... 

Other metal derivatives can be used for coupling. Among the more popular reagents are allyl- or alkyl-metallic compounds of tin and titanium. Allylsilanes can also be used if a Lewis acid is added. 

Fig. I. Apparatus for isolation of alkyl metal compound by distillation.

Carboxylation reactions with the hard Lewis acid CO2 are of potential interest for future industrial syntheses. Understandably, the hardest alkyl metal compounds are required to facihtate reactions of the type ... 

Other protonic reagents also cleave alkyl metal compounds. Calvin and Coates 18) report that benzenethiol and even p-nitrophenylacetylene cleave a dimethylpalladium compound. 

This process is simply the reverse of the olefin insertion reaction by which several alkyl metal compounds have been made (Section II,D). The elimination of ethylene from the ethylplatinum compound can be reversed under ethylene pressure (50). The elimination reaction appears to be involved in the formation of three extraordinarily reactive transition metal hydrides. 

Cyclopentadienylaryl or cyclopentadienylalkyl derivatives of cyclopentadie-nyltitanium obtained by the reaction of cyclopentadienyltitanium with aryl metal compounds or alkyl metal compounds, are also stable by the stabilization action of the cyclopentadienyl ring. For example, Cp2TiCl2 reacts with phenyllithium to give the diphenyl derivatives. This compound decomposes at 105 °C to yield benzene [21]. 

A large number of articles survey the ch stry, biochemistry, and toxicology of methylmercury and other alkyl-metal compounds. Four deal specifically with aspects of Minimata disease, - one with the role of methanogenic bacteria in the alkylation of arsenic and mercury, and one on the general microbial alkylation of metals. ... 

The importance of the contamination of metathesis mixtures by H2O or O2 has been shown by Muetterties et al. [52], who observed that [WCy, in combination with different alkyl metal compounds, was inactive at room temperature for the metathesis of acyclic internal alkenes, when the reaction was performed in an atmosphere free of water and oxygen. 

In ref. 127) alkylcobalt tetracarbonyls are specified rather than the more general term alkyl metal compound used by us. However, there seems to be no reason why for the sake of discussion the suggested equilibrium proposed for alkylcobalt tetracarbonyls might not be extended to include alkyl transition metal compounds as a whole. 

Very recently, a comprehensive review appeared showing the scope of crosscoupling reaction of the challenging alkyl metal compounds. " ... 

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