Chapter 7 - Aliphatic Organometallic and Organometalloidal Compounds

Abstract

This chapter describes the aliphatic compounds that contain a bond between a carbon atom, and a metal or metalloid. Transition metal compounds, which contain olefins and acetylenes bonded to the metal, are also discussed. The nature of the carbon–metal bond has a large influence on the reactivity and properties of organometallic compounds. Alkali metal alkyls can be grouped into two classes: lithium alkyls and derivatives of sodium, potassium, rubidium, and caesium, which behave in many ways as salts. The most important derivatives of the Group II metals are the Grignard reagents. They owe their great utility in synthesis to the fact that they are easily formed in high yields from metallic magnesium, are soluble and stable in ether, and are very reactive. Group IIIB elements such as boron, aluminum, gallium, indium, and thallium form well-defined alkyl compounds that show marked variations in reactivity. Organic derivatives, Group VB that shows a striking gradation in properties as the element becomes more metallic, from compounds of phosphorus, which are very stable, to the unstable compounds of bismuth. The derivatives of selenium and tellurium closely resemble those of sulfur, and also of arsenic and antimony in Group VB. There is usually no relation between the electronegativity values given for transition metals and the chemical properties of their alkyl derivatives.