Arsenic-75, Antimony-121,123 and Bismuth

The preparation and reactivity of various ionic alkyl and aryl Group 15 complexes have been reported. For example the [(Bu P)3As] anion reacts with [CpMo(CO)3Cl], M = Mo, W, to give [(C5H4 As(PBu )3 )M(CO)3Cl] (X-ray) via the elimination of LiH rather than the expected product resulting from Cl 

Ohhata, M. Miyoshi, R. Tanaka, T. Minami, F. Ozawa and M. Yoshifuji, Angew. Chem. Int. Ed. Engl, 2000, 39,4512. 

Kleinebekel and T. Haase, Z. Anorg. Allg. Chem., 2000,626,1857. 

Arsenic vapour cmitains AS4 molecules, and the unstable yellow form of solid As probably also contains these units. At relatively low temperatures, Sb vapour cmitains molecular Sb4. At room temperature and pressure. As, Sb and Bi are grey solids with extended structures resembling that of black phosphorus (Fig. 15.3c). On descending the group, although intralayer bond distances increase as expected, similar increases in interlayer spacing do not occur, and the coordination number of each atom effectively changes from 3 (Fig. 15.3c) to 6 (three atoms within a layer and three in the next layer). 

Arsenic, antimony and bismuth bum in air (eq. 15.13) and combine with halogens (see Section 15.7). 

Like N2, P4 can act as a ligand in J-block metal complexes. Examples of different coordination modes of P4 are shown in structures 15.11-15.13. 

Arsenic, Antimony, and Bismuth.- (Diphenylarsino)methyl-lithium (203) has been prepared by either halogen-lithium or tin-lithium exchange from (204) or (205) respectively. Interestingly the reactivity of (203) depends on the method of preparation used, although the reasons for this are not known. A stereoselective synthesis of JE-a, -unsaturated aldehydes has been achieved by reacting aldehydes with the arsonium salt (206) in the presence of a weak base. The ylide derived from (206) shows a reasonable 

Allylic halides react with aldehydes and metallic bismuth to 

Arsenic and antimony are classed as metalloids or semi-metals and bismuth is a typical B subgroup (post-transition-element) metal like tin and lead. 

The halides of arsenic, antimony and bismuth illustrate the following trends down the Group (a) increasing metallic character of the elements (b) the inert pair effect—that is, the tendency towards an increased stability of the Group number minus two oxidation number (+3) (c) a tendency to higher coordination numbers. 

All the trihalides, MX3 (M = As, Sb, Bi X = F, Cl, Br, I) are known. They are all solids except for ASF3 and ASCI3 which are liquids at room temperature, and they are rapidly hydrolysed. 

How many different types of fluorine atom are there in liquid SbF5  

The reaction of 2-Ph-4-HO-arsabenzene (8) with Ph% produced thermally from PhgHg, gave (6, = R = Ph) treatment of (6) with AcgO provided 

RgSbBr and Mg (R = Me or Et) and from RjSb and Na, followed by reaction with NHiBr. 

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A complete set of trihalides for arsenic, antimony and bismuth can be prepared by the direct combination of the elements although other methods of preparation can sometimes be used. The vigour of the direct combination reaction for a given metal decreases from fluorine to iodine (except in the case of bismuth which does not react readily with fluorine) and for a given halogen, from arsenic to bismuth. 

Give an account of the oxides and the chlorides of arsenic, antimony and bismuth, including an explanation of any major... 

Metals less noble than copper, such as iron, nickel, and lead, dissolve from the anode. The lead precipitates as lead sulfate in the slimes. Other impurities such as arsenic, antimony, and bismuth remain partiy as insoluble compounds in the slimes and partiy as soluble complexes in the electrolyte. Precious metals, such as gold and silver, remain as metals in the anode slimes. The bulk of the slimes consist of particles of copper falling from the anode, and insoluble sulfides, selenides, or teUurides. These slimes are processed further for the recovery of the various constituents. Metals less noble than copper do not deposit but accumulate in solution. This requires periodic purification of the electrolyte to remove nickel sulfate, arsenic, and other impurities. 

F. G. Mann, The Heterocyclic Derivatives of Phosphorus, Arsenic, Antimony and Bismuth, 2nd ed., Wiley-Interscience, New York, 1970. 

G. O. Doak and L. D. Freedman, Organometallic Compounds of Arsenic, Antimony, and Bismuth,]ohn Wiley Sons, Inc., New York, 1970. 

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. 

By-Product Recovery. The anode slime contains gold, silver, platinum, palladium, selenium, and teUurium. The sulfur, selenium, and teUurium in the slimes combine with copper and sUver to give precipitates (30). Some arsenic, antimony, and bismuth can also enter the slime, depending on the concentrations in the electrolyte. Other elements that may precipitate in the electrolytic ceUs are lead and tin, which form lead sulfate and Sn(0H)2S04. 

Arsenic, Antimony and Bismuth Table 13.4 Some physical properties of Group 15 elements... 

C. A. McAulifee and A. G. Mackie Chemistry of Arsenic, Antimony and Bismuth, Ellis Horwood, Chichester, 1990, 350 pp. 

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