Antimony carbon—bismuth bonds

We have essentially exhausted all of the directly measured enthalpies of formation of compounds containing carbon-arsenic, -antimony and -bismuth bonds. However, let us now make use of other thermochemical data and see what can be derived using some plausible estimates. And barring that, let us see what new enthalpies of formation would become available if only some new measurement were made. 

Only a few compounds containing six carbon-antimony or -bismuth bonds are known. The first compound of this type was obtained as colorless crystals by Wittig and Clauss from PhjSb and PhLi (equation 177 ). The ate complex 66 reacts with water forming PhsSb. 

Many of the properties of the group 15 element diheteroferrocences are very similar to ferrocenes and other metallocenes. It seems justified to regard the diheteroferrocenes as perturbed ferrocenes just as we regard the group 15 heterobenzenes as perturbed benzenes. Thus, it is very clear that the elements phosphorus, arsenic, antimony, and bismuth can take part in 7r-bonding in a manner similar to carbon. 

Carbon functional groups, attachment to polysilanes, 3, 585 Carbon-heteroatom bond formation via antimony(III) compounds, 9, 428 via antimony(V) compounds, 9, 432 via bismuth(III) compounds characteristics, 9, 440 with copper catalysts, 9, 442 non-catalyzed reactions, 9, 443 with bismuth(V) compounds, 9, 450 with bismuthonium salts, 9, 449 with bismuth ylides, 9, 450 Carbon-heteroatom ligands in tetraosmium clusters, 6, 967 in tetraruthenium clusters, 6, 960... 

Metal-carbon multiple bonds, arsenic, antimony, bismuth,... 

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... 

Regarding antimony and bismuth, only a few studies exist involving organometallic compounds with metal-carbon bonds. Hence in these cases inorganic and organic compounds with metal—O—C bonds are also described. 

This chapter is concerned with the solid state structures of arsenic, antimony and bismuth compounds, which in general contain at least one bond between carbon and the Group 15 element. In selecting material for discussion, I have been greatly aided by the availability of the Cambridge Crystallographic Data Base. The period under consideration covers effectively the years between 1981 and 1992. 

What type of compounds will be covered in this overview. Strictly, only compounds which have at least one metal-carbon bond (with the exception of metal carbides) are called organometaiiic. However, this definition was not adopted in this chapter because many families of compounds that are relevant in organometaiiic chemistry would not be included (e.g., alkoxides). By metal we mean any element from groups 1 (except hydrogen), 2, 3 (including lanthanides and actinides), 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 (except boron), 14 (except carbon and silicon), and 15 (antimony and bismuth only). Most of the available thermochemical data for all these species are freely available in a single on-line database the NIST Chemistry WebBook Unless stated otherwise, all the data included in this chapter were quoted from that reference. 

Preparative aspects. Since bonds between carbon and arsenic, antimony and bismuth are stable to water they may be made in aqueous solution. Thus, alkyl arsonic adds RAs(OH)2 may be prepared by the Meyer reaction between sodium arsenite and alkyl halides ... 

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