Element-carbon bonds

Direct metallation of o-halogenophenoxyelement derivatives of silicon, tin, and phosphorus leads to an unstable metallated intermediate which undergoes a rapid 1,3-rearrangement under element-carbon bond formation. This type of reaction seems to be a general method for the synthesis of hydroxyphenyl element derivatives [1-4], We have studied the influence of different organoelement groups on the reaction pathway. The yield increases in the sequence R3Sn < R2P < RjSi P(0)(0R)2. 

Certain metal alkyl compounds from p- and d-block elements react under very mild conditions with 1 under insertion into the element-carbon bond. Some examples are shown in Scheme 9. 

These names are used in oi anic substitutive nomenclature for situations in which the substituent group is joined to the parent skeleton by a single element-carbon bond. 

Organoelement groups like the phenylthio- or diphenylarsanyl group can be removed reductively from alkyl residues very well by Raney-Nickel (Scheme 8). But the transfer of this splitting reaction to our products of anionic cycloadditions - pyrrolidine derivatives - led to difficulties because, as demonstrated in Scheme 8, in addition to the splitting of the element carbon bond ring opening or aromatization occured. 

Note that while homolysis of the element-carbon bond is as a rule not characteristic for allylic derivatives, similar cyclopentadienyl tin and lead derivatives undergo a direct photolysis with Cp radical abstraction57. ESR spectra taken in the photolysis of... 

Antimony and bismuth lie at the fifth and sixth rows of the 15th group in the periodic table, and a variety of trivalent and pentavalent organic compounds derived from these elements have been reported. As shown in Table 1, antimony and bismuth have relatively small ionization potentials and electronegativities as well as large orbital radii. Due to these properties, elemental antimony and bismuth behave as metals, and the respective organic compounds possess relatively weak and polarized element-carbon bonds. These characteristics of antimony and bismuth have been... 

Several B metals, the borderline metal Co, and all metalloid metals can form element-carbon bonds that are stable in water. Metallorganic compounds of A ions and of borderline ions (exception Co) hydrolyze in contact with water. Methylation and alkylation are common reactions in biological systems they may also proceed abiotically and generate methyl- or alkyl-element compounds. Examples include selenide, selenoamino acids, methylarsenic acid (MM A A), and dimethylarsenic acid (DM A A) ... 

The following sections are organized by the group on the metal to which a molecule is inserting. Thus insertions into element-hydrogen bonds, insertions into element-carbon bonds, etc., are covered separately. 

Insertion Reactions into Element-Carbon Bonds 11.3.1. Introduction... 

A 1,2-insertion of an unsaturated substrate into an element-carbon bond can also be regarded as adding an element-carbon bond across the substrate multiple bond. This transformation is a fundamental step in industrial oligomerization and polymerization reactions For unsymmetrical substrates, X=Y, two regioisomers may form ... 

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