Organoantimony compounds

Fewer organoantimony compounds containing hydrogen-bonds leading to supra-molecular self-organization have been described. It can be expected that many analogies with organotin compounds are possible and perhaps this will stimulate a search for such structures. 

5 Supramolecular Self-Assembly by Hydrogen-Bond Interactions 

The hydroxophosphinate [Me3Sb(0H)(02PPh2)] is a chain-like supramolecular array formed by P=0- H-0 hydrogen-bonding, 39 [94]. 

In / -oxo-bis(trimethylantimony) benzenesulfonate hydrate, [Me3Sb0H2]0 -(03SPh)2, 40, hydrogen-bonds are present between the coordinated water and discrete anions [95]. 

Organic derivatives of antimony can be prepared in essentials in the same way as the arsenic analogs e.g., trialkylstibines are formed by the action of alkyl iodides on antimony-potassium alloy 512 

More suitable for, especially, the triarylstibines of higher molecular weight, is the reaction of aryl halides, antimony trichloride, and an excess of sodium in benzene or xylene, as discovered by Michaelis and Reese 513 ether cannot be used as solvent as the necessary reaction temperature cannot then be attained.514 

Tris-(4-iw-xylyl)stibine 514 4-Bromo-m-xylene (56 g) and antimony trichloride (23 g) are dissolved in dry benzene (150 ml), and then metallic sodium (50 g in pieces) is added. When the reaction is complete (usually after warming) the solution is set aside overnight and then filtered. The residue is extracted three times with boiling benzene. All the liquids are united and the benzene is removed, whereafter the oily residue is poured into anhydrous ethanol. In a few minutes the stibine separates as long needles (25 g, 57 %). 

Formation of metal-carbon bonds (organometallic compounds) 

Trialkenyl- and trialkynyl-stibines, e.g., tris(perfluorovinyl)-,489 triethynyl-,490 and tris(phenylethynyl)-stibine,401 have been synthesized by this method. 

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This reaction gives fair-to-good yields of monoorganotin tribromides and trichlorides when quaternary ammonium or phosphonium catalysts are used (149). Better yields are obtained with organic bromides and staimous bromide than with the chlorides. This reaction is also catalyzed by tri alkyl antimony compounds at 100—160°C, bromides are more reactive than chlorides in this preparation (150,151). a,C0-Dihaloalkanes also react in good yield giving CO-haloalkyltin trihaHdes when catalyzed by organoantimony compounds (152). 

Metallic Antimonides. Numerous binary compounds of antimony with metallic elements are known. The most important of these are indium antimonide [1312-41 -0] InSb, gallium antimonide [12064-03-8] GaSb, and aluminum antimonide [25152-52-7] AlSb, which find extensive use as semiconductors. The alkali metal antimonides, such as lithium antimonide [12057-30-6] and sodium antimonide [12058-86-5] do not consist of simple ions. Rather, there is appreciable covalent bonding between the alkali metal and the Sb as well as between pairs of Na atoms. These compounds are useful for the preparation of organoantimony compounds, such as trimethylstibine [594-10-5] (CH2)2Sb, by reaction with an organohalogen compound. 

Organoantimony Compounds with Five Sb—C Bonds. A number of pentaalkyl- and pentaalkenylantimony compounds have been prepared from tetraalkyl- or tetraalkenylstibonium hahdes and alkyl or alkenyllithium or Grignard reagents, for example ... 

M. Wieber, Gmelin Handbook of Inorganic Chemistry, Sb Organoantimony Compounds, Part 1, 8th ed., Spriager-Vedag, Berlin, Germany, 1981. 

An intriguing 3-coordinate organoantimony compound, which is the first example of trigonal-planar Sb, has been characterized. " The stibinidene complex [PhSb Mn(CO)2(rj -CsH5))2] has been isolated as shiny golden metallic crystals (mp 128°) from the crown-ether catalysed reaction ... 

Antimony battery grids, composition, 3 52t Antimony bromide sulfide, 3 63 Antimony chloride oxide, 3 62t Antimony compounds, 3 56-87 analysis, 3 80-81 environmental impact, 3 81 health and safety factors, 3 81 inorganic, 3 57-67, 62t organoantimony compounds, 3 67—80... 

Scheme 18 Cross-coupling reaction of Ar3Bi with organoantimony compounds...

The chemistry of antimony is generally less well developed than that of arsenic and particularly in respect of Group 4 ligands. For the purposes of this discussion organoantimony compounds will be dealt with first and those of silicon, germanium, tin and lead will be taken together. 

Table 11 Bond Lengths and Angles for Some Organoantimony Compounds...

It is notable that the existence of configurational isomers in solution has been established for these hexacoordinate organoantimony compounds, since among hexacoordinate organotin compounds, the structures of which have been extensively studied, there are few reports of such isomers.4... 

In contrast to the well-studied triorganophosphine oxide or sulfide, very little work had been done on the analogous organoantimony compounds. 

Reactions of trimethylstibine sulfide with alkyl halides proceed smoothly under mild conditions to give dialkyl disulfides and organoantimony compounds in quantitative yields 25) ... 

Trialkylstibines. These organoantimony compounds are obtained by reaction of RMgX with SbClv... 

The first organoantimony compound, triethylstibine, was reported in 1850. Since then, a wide range of compounds with antimony mainly in the +3 and +5 oxidation states was studied. In this article, the focus is mainly on the results published between 1993 and 2003. Several general overviews of the chemistry of organoantimony compounds were presented in this period in books and aimual... 

Organoantimony compounds with bonds between Sb and group 13 elements were discussed in a recent review. They are known as Lewis acid-base adducts R3Sb-MR3 (M = Al, Ga, In) and as four- or six-membered heterocycles (R2Sb-MR2) (n = 2, 4). Pyrolysis of these compounds leads to the semiconducting materials AlSb, GaSb, and InSb. 

Low-coordination organoantimony compounds are species with the coordination numbers 1 or 2 at the antimony centers, for example, stibinidenes R-Sb, distibenes R-Sb=Sb-R, stibaalkenes, R-Sb=CR2, or cyclic compounds. Stable monomeric stibinidenes or stibaalkenes are not known. Complexes with stibinidene ligands are, however, well established, and trapping of a sterically hindered stibinidene, RSb, R = 2,4,6-(MesSi)2CH]3C6H2 is achieved as a cycloadduct... 

Several methods for the determination of antimony in organoantimony compounds have been described In one, the organoantimony compound is burnt with metallic magnesium to convert antimony to magnesium antimonide . This is then... 

Marr and coworkers have described a procedure for the microdetermination of antimony in organoantimony compounds by atomic absorption spectrophotometry. They compared air-acetylene and air-hydrogen flames and prefer the latter on account of the lower noise. The effects of varying instrumental and chemical parameters were also studied. 

A number of relatively involatile organoantimony compounds and inorganic antimony salts were analysed by the proposed method and also by an alternative spectrophoto-metric method. 

Many organoantimony compounds are not particularly soluble in ethanol and it is necessary to use a second organic solvent to assist dissolution of the samples. The effect of... 

The results obtained for the analysis of a number of organoantimony compounds by the atomic absorption and the spectrophotometric methods are summarized in Table 24. The results obtained by the two rnethods are generally in good agreement. 

Besada and Ibrahim have described a polarographic method for the determination of antibilharzial organoantimony compounds in river waters. 

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