Section 10. Arsenic, Antimony, Bismuth

In the first section of this chapter some of the properties of the elements hydrogen, carbon, nitrogen, phosphorus, arsenic, antimony, bismuth, oxygen, sulfur, selenium, tellurium, fluorine, chlorine, bromine, and iodine are described. The following sections are devoted to some of their compounds with one another, especially the single-bonded normal-valence compounds. Compounds of nonmetals with oxygen are discussed in the following chapter. 

The precipitated copper from this reaction is an important constituent of the slime that collects at the bottom of the electrolytic cells. The accumulation of copper as well as of impurities such as nickel, arsenic, antimony, and bismuth is controlled by periodic bleed-off and treatment in the electrolyte purification section. 

CHEC-II(1996) comprehensively outlines the most commonly used synthetic approaches applied to these types of bicyclic compounds of phosphorus, arsenic, antimony, and bismuth <1996CHEC-II(8)863>. The six classes of compounds listed in this section have received considerable attention over the review period and as such the principal synthetic methods for these compounds are discussed. Schoth et al. <2000CCR101> have reviewed the use of fluorinated 1,3-diketones, 2-trifluoroacetylphenols, and their derivatives in the synthesis of phosphorus compounds. Included in this review is the use of these reagents for the synthesis of various [3.3.1] nonfused and [3.3.0] fused phosphorus bridgehead bicyclic systems. 

This chapter will be divided into three main sections, dealing with the chemistry of arsenic, antimony and bismuth individually, since their interest is intrinsic rather than comparative. However, the Periodic Table trends are important and their main features will be outlined. 

These compounds are discussed in the Sections on Phosphorus, Arsenic, Antimony, and Bismuth Tellurolates (s.p. 198, 199). 

The first part of this section deals with complex compounds with arsenic, antimony or bismuth acting as central atoms. They have been ordered according to the coordination number of the element and, within these sections, according to the donor properties of the ligands and to an ionic or covalent type of the complex. In the second part we report on organoelement compounds coordinated to transition metals or main group elements. 

The more detailed discussion which follows is divided into separate sections on arsenic, antimony and bismuth compounds, and these are further sub-divided first on the basis of the oxidation state and then in terms of the specific elements attached. 

Arsenic, antimony and bismuth burn in air (equation 14.11) and combine with halogens (see Section 14.7). 

Radical chemistry has not played an important role in the heterocyclic chemistry of arsenic, antimony, or bismuth compounds. However, arsolyl radicals (e.g., (39), (40)) are proposed intermediates in alkylations (Section 2.16.5.3.2) and are observable by ESR during the formation of radical anions (Section 2.16.10.1) such as (36) <72AG(E)439, 83JOM(249)335>. 

Conformational properties of these heterocyclic systems usually result from the increased CN numbers of arsenic, antimony, and bismuth. Tricoordinate systems show interesting solid state conformational behavior as displayed in l,l -biheteroles (Sections 2.16.10.2 and 2.16.11.2) and organometallic complexes (Section 2.16.10.3). More detailed treatment of this subject is found in the references in these sections. 

Unfortunately, arsenic, antimony, or bismuth chemistry has no reaction analogous to the McCormack reaction for the synthesis of phospholenes and phospholes (see Section 2.15.10.3). 

Arsenic, antimony, and bismuth display a wide variety of CN, and their syntheses, where ring formation is the primary process, are included here. Formation of oxides, methiodide salts, and halogen derivatives subsequent to ring formation are included in the appropriate reactivity sections. 

Preparation of 1,1 -biheterole systems containing arsenic, antimony, and bismuth has been important in understanding thermochromic behavior in terms of structure and bonding. Their interesting solid state structures help explain why some show color transitions, while others do not (see Section 2.16.11.2). The coupled products are sometimes very air-sensitive, but can be isolated by low temperature crystallization for nonpolar solvents or by sublimation. The biarsoles, bistiboles, and bibismoles tend to be thermally stable, while the bibismolanes usually decompose at room temperature. In this section, the different methods by which these compounds may be prepared and isolated are examined. 

Nitrogen is the most important of the group 5A elements. Of the other elements in this group—phosphorus, arsenic, antimony, and bismuth—phosphorus has a central role in several aspects of biochemistry and environmental chemistry. In this section we will explore the chemistry of these other group 5A elements, with an emphasis on the chemistry of phosphorus. 

Wood s metal Bismuth, lead, tin, cadmium 46 Arsenic, Antimony and Bismuth bismuth section... 

The structures of antimony and bismuth correspond to that of gray arsenic. With increasing atomic weight the distances between adjacent atoms within a layer and between layers become less different, i.e. the coordination polyhedra deviate less from a regular octahedron. This effect is enhanced under pressure (cf. next section). 

Antimony and bismuth bonds to arsenic are dealt with in Sections 28.10.2 and 28.16.2 under antimony and bismuth, respectively. 

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