Bismuth complexes halogen

From the structural standpoint these compounds are closely related to the complex bismuth oxyhalides (p. 716) in which the square Bi202 layers are interleaved with halogen layers. A great variety of compounds can be prepared, for example, (MBi)gR40i 6, in which M can be Na, K, Ca, Sr, Ba, or Pb, and R is Ti, Nb, or Ta. Note that compounds of this family such as Bi2Ta05F are quite unrelated to those described on p. 720, for example, BiTa20gF. 

FIG. 20.6. The structures of complex bismuth oxyhalides. (a) Metal-oxygen sheet viewed in directions parallel and perpendicular to the sheet, (b), (c), (d) Elevations of structures built from (b) single halogen layers Xj, (c) double halogen layers Xj, and (d) triple halogen layers... 

Other oxyhalides, mostly oxychlorides and oxybromides, result from the controlled hydrolysis of the trihalides, and are of interest for two main reasons. First, they are quite unrelated to the oxyhalides of bismuth. Although both antimony and bismuth form compounds MOX the structures of the antimony compounds are quite different from those of the compounds BiOX, which have been described on p. 408. The more complex oxyhalides of Sb have no analogues among Bi compounds. Second, a feature of the published structures of the antimony oxyhalides is the coordination of Sb by either three or four O atoms. It should perhaps be remarked here that the investigation of the structures of these complex compounds is difficult, and the precise positions of the O atoms are by no means certain. However, it appears that a feature of these compounds is the formation of extended Sb—O systems, generally layers, interleaved with halogen... 

Adducts of the l,2-dithiole-3-thione with silver nitrate and copper dichloride have been described, and for various l,2-dithiole-3-thiones, adducts containing iron, cobalt, nickel, and copper have been studied in more detail. The ligands (L) used are either unsubstituted l,2-dithiole-3-thione or its methyl- or aryl-substituted derivatives. If X represents a halogen atom, the following types of coordination compounds have been characterized CuXLj and CuXLa, FeXjLj, CoXaL, and NiX Lj. Complexes of titanium(III), tin(IV), antimony(III) and (V), and bismuth(III) have also been studied. ... 

I.r. data for the pyridine, bipyridyl, and terpyridyl complexes of arsenic, antimony, and bismuth(m) halides have been interpreted in terms of halogen bridging in the bipyridyl species, but the terpyridyl compounds are formulated as [SbX2(terpy)]2 SbXj, TAsCUfterpyir ASCI4, and [AsBr2(terpy) ]Br. The bismuth adduct BiCl3,terpy, on the other hand, is covalent. 

Miscellaneous capping agents X are used for LRP. Examples are listed in Scheme 7.2. They include sulfur compounds (Schemes 7.2a and 7.2g), stable nitroxides (7.2b),stable nitrogen and carbon compounds (7.2c),transition metal complexes (7.2d), iodine (7.2e), halogens with transition metal catalysts (7.2f), and tellurium, stibine, and bismuth compounds (7.2h)." ... 

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