Antimony, elemental reactions with

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. 

As with the previous element, the dangerous reactions of antimony derivatives are linked to the behaviour of the anion. The element is reducing and apart from its interaction with two metals it gives rise to dangerous reactions with strong oxidants. 

Certain volatile elements must be analyzed by special analytical procedures as irreproducible losses may occur during sample preparation and atomization. Arsenic, antimony, selenium, and tellurium are determined via the generation of their covalent hydrides by reaction with sodium borohydride. The resulting volatile hydrides are trapped in a liquid nitrogen trap and then passed into an electrically heated silica tube. This tube thermally decomposes these compounds into atoms that can be quantified by AAS. Mercury is determined via the cold-vapor... 

Objections against these findings were soon raised. The strongest peak attributed to element 126 could experimentally be accounted for [55] by a prompt y-ray from the (p,n) nuclear reaction with natural 140Ce, a major component of the monazite crystals. The weaker peaks were shown to stem from to K x-rays from traces of ordinary elements such as antimony and tellurium [56]. When a more specific technique for the excitation of x-ray spectra was applied to the inclusions, namely by monochromatic synchrotron radiation tuned to the x-ray absorption edges, the evidence for superheavy elements vanished [57,58]. Furthermore, attempts failed [59] to detect them in bulk monazites through isolation of an A>294 fraction with a mass... 

The reaction very likely proceeds through the disproportionation of 4-ethoxyphenyl tellurium monochloride to tellurium and the diaryl tellurium dichloride. Bis[trifluoromethyl] tellurium transferred its trifluoromethyl groups to iodine, sulfur, selenium, phosphorus, arsenic, and antimony on heating with the elements, sulfur dichloride, selenium tetrabromide, or the triiodides of phosphorus, arsenic, and antimony at 170 to 220° in sealed tubes3. 

Single crystal X-ray analysis of the ethynyl-l,5-azastibocine 5a showed the presence of intramolecular Sb---N interaction which should be responsible for the reactivity enhancement of the ethynyl-l,5-azastibocines in Pd-catalyzed cross-coupling reactions with organic halides (see Section 14.18.11). The distance between the antimony and nitrogen atoms (2.538(4) A) corresponds to 68% of the sum of the van der Waals radii of both elements (3.74 A). In the crystal central antimony atom exhibited a pseudo-trigonal-bipyramidal structure <2003TL8589>. 

Of the higher main group (V) elements, only P-centered radicals have been used in intermolecular radical additions to alkynes, whereas radical reactions with the unpaired electron located at the higher metallic elements arsenic, antimony, and bismuth have not been reported. 

Antimony pentachloride, SbCh, is a liquid (mp 4°C, bp 140 °C dec ), which can be obtained by reaction of SbCls with elemental chlorine. Sohd SbCls exists in two modifications above 54.1 °C, it is trigonal bipyramidal, below this temperature, it changes reversibly into a double chlorine-bridged dimer. SbCls decomposes at 140 °C with formation of SbCls and CI2. It is a Lewis acid with a strong tendency to interact with a ligand (L) to give octahedral complexes LSbCls. Reactions with chloride ion donors lead to ionic compounds with SbCle" anions and unusual cations. Examples are shown in equations (10) and (11). 

The arsenic and antimony pentahalides EX5 (E group 15 element As or Sb X = F or Cl) are strong, irreversible oxidants the gas AsFs has little been used, but SbCF and SbFs are commercially available, very air-sensitive liquids which are used in dry and deoxygenated dichloromethane and liquid sulfur dioxide respectively. SbCls is easier to handle than SbFs which gives the dangerous HF by reaction with moist air. Moreover, SbCls is conveniently used in dichloromethane whereas SbFs is best used in liquid SO2. On the other hand, the side products (halogenation) are more frequently encountered with SbCls than with SbFs. The redox process follows ... 

The intermediate of the irreversible isomerization can be isolated. The EMc2 unit is <7 bonded in the educt it is a centre of basic activity, shoeing tendency for reactions with electrophiles. Thus the electron-rich state of the atoms of group 15 elements leads to irreversible isomerization with shifting of one methyl group from the PR3 ligand to arsenic or antimony, respectively. The donor capacity of the transition metal is enlarging this ability. 

The individual elements produced various results. Additions of antimony oxide, tin(ll) oxide, and samarium oxide gave no evidence of reactions with the nitrate melt or solubility. The addition of zirconyl nitrate resulted in the evolution of nitrogen dioxide from the melt and the formation of a white insoluble precipitate. Addition of palladium nitrate to the melt produced a black melt and black insoluble solids. Dissolution of the cooled and solidified salt cake with distilled water indicated that a palladium mirror had formed at the meniscus of the melt. Niobium was added as potassium hexaniobate, KgNb Oj I6H2O. 

Davy reported that elemental arsenic and antimony both react with phosgene, upon heating, to produce their respective chlorides and carbon monoxide [467]. Phosphorus, however, can be sublimed in an atmosphere of phosgene without any reaction occurring [467]. 

Oxidation Reactions with Antimony Pentafluoride. An appropriate amount of the finely powdered element is introduced into A (Fig. 

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