Antimony halides

Pentacovalent Antimony Halides and Related Compounds. Antimony hahdes of the types RSbX, R2SbX3, R2SbX2, and R SbX, where X is a halogen, are known, but compounds of the first type have only been isolated and characterized where R is aryl. Tetrachloromethylantimony has been prepared at —70°C, but not isolated (167) ... 

Electrolysis of acidified, stirred antimony halide solutions at low current density produces explosive antimony which contains substantial amounts of halogen. 

Antimony dichloride trifluoride, 3 62t Antimony dioxide, 3 59 Antimony graphite fluoride, 3 63-64 Antimony halides, physical properties of, 3 61t... 

The arsenic and the antimony halides, that have lone electron-pairs, too, form compounds similar to that of PC13, but less stable, and the bismuth halides do not react at all. The most probable explanation is that, in the series... 

Aluminum trichloride and boron trifluoride as additives have a similar effect on the fluorination of (trichloromethyl)benzene by antimony(III) fluoride. With the additives, the reaction starts even at O C but no exchange is observed in the absence of the catalysts.12 The relative exchange reactivity order of the antimony halides is as follows antimony(III) fluoride < anti-mony(III) fluoride + antimony/V) chloride < antimony(V) dichlorotrifluoride, antimony/V) di-bromotrifluoride < antimony/V) fluoride.3... 

These molecules are usually formed by reacting antimony halides with an organosulfur compound (equations 43,124 44 26 and 45125). 

The pseudohalides are discussed in the halogen ligand section rather than in the nitrogen ligand section because in the majority of the examples studied the pseudohalide is the minor ligand, i.e. one among many—most studied are antimony halide pseudohalides. 

Hydrogen bonding is so common that coordinate bonds between other elements are sometimes overlooked. Antimony(Ill) halides form very few complexes with other halides, whereas aluminum halides readily form complexes. The octet of electrons is complete in all atoms of the antimony halides, but is incomplete in die aluminum atom of aluminum halides ... 

Antagonism between antimony oxide and phosphorus flame retardants has been reported in several polymer systems, and has been explained on Ihe basis of phosphorus interfering with the formation or volatilization of antimony halides, perhaps by forming antimony phosphate. 

Stannoles differ significantly from other group 14 metalloles in their ability to undergo exchange reactions with boron, arsenic or antimony halides. Boroles563,76, arsoles and... 

Diethylgold bromide, 1666 Dimethylantimony chloride, 0896 Dimethylbismuth chloride, 0889 Ethylmagnesium iodide, 0855 Methylmagnesium iodide, 0445 Methylzinc iodide, 0446 ALKYLALUMINIUM HALIDES GRIGNARD REAGENTS TRI Al, KYI,ANTIMONY HALIDES... 

In the reaction of trimethylstibine sulfide with acid halide, trimethyl-antimony halide thiocarboxylates (XIII), corresponding to compound XII in Eq. (1) were isolated 27) ... 

Wittig s work was later confirmed and extended by Russian, Dutch, and Japanese groups, who were able to prepare other pentaalkylantimony compounds using his method, which consisted of the reaction of trialkyl (or tetraalkyl) antimony halides with alkyllithium reagents. Table IV lists some of the important examples. 

The role of antimony halides as flame-retardant species in the gaseous phase is well established when SbX3 (X = chlorine or bromine) is introduced into premixed methane-oxygen flames, atomic antimony and antimony monoxide are found in the flame.43 Sb203 was shown by mass spectrometry to be present only in the preflame zone and no antimony-halogen species could be detected in the flame itself. 

Like triorganoantimony(V) halides, derivatives of this class had also been prepared in the middle of nineteenth century169-171). The procedure adopted, which is still the principal method for preparing the tetraalkyl antimony halides involves the quaternization of trialkylantimony with an alkyl halide13,172). Since the triarylantimony as well as diaryl-alkylantimony can not be quatemized by alkyl halides, other methods13,21,23,98,173 179 e.g., the reaction of triphenylstibine, chlorobenzene and anhydrous aluminium chloride179), have been utilized to prepare these derivatives. 

Several intermediate antimony halides, such as (SbF3)I(SbF5)y, with jc = y — 1 x = 6 and y = 5 x = 2 and y = 1 x = 3 and y = 1 are known. Their existence, and their structures, depend on the high fluoride ion affinity of SbF5, whereby SbF6 and Sb2F i ions and complex polymeric cations, such as (Sb3Fg ) are formed. 

Table 2. Synthesis of Fluorohaloalkanes through Halogen Exchange with Antimony Halides/Hydrogen Fluoride...

Antimony halides R SbX3 (n = 1, 2) react with magnesium to form Grignard-type reagents R Sb(MgX)3 n = 1, 2) (equations 115 and 116 ), but the yield is usually low because the method also gives Sb—Sb compounds vide infra). 

Finally here, it is useful to note that arsenic tribromide forms a 2 1 complex with hexaethylbenzene , with a structure similar to those of the Menshutkin complexes, obtained from antimony halides and arenes (see Section III.A.6). Complex formation between AsClj and both 15-crown-5 and [2.2.2]paracyclophane has also been investigated. 

Mesitylene " and hexaethylbenzene each give 1 1 complexes with half-sandwich structures with antimony trichloride and a similar 1 1 complex is known for the tribromide with mesitylene. The 2 1 adduct of antimony tribromide with biphenyl is centrosymmetric with a molecule of the antimony halide coordinated to each phenyl group and on opposite sides a similar picture is found with 2SbCl3.(2,2 -dithienyl), 2SbBr3-(9,10-dihyd-roanthracene) and 2SbCl3. (pyrene) . In the complex of [2.2.2]paracyclophane with two molecules of SbCl3, two of the benzene rings are almost symmetrically coordinated to antimony . 

Bismuth trichloride forms a 1 1 Menshutkin-like complex with mesitylene " and a 2 1 complex with hexamethylbenzene , in which the arene is bonded to bismuth at distances to the ring centre of ca 3.1 A. As with the related antimony complexes, there are also a number of intermolecular chlorine bridges, raising the bismuth coordination number and leading to either sheets or tetrameric bismuth chloride networks. These compounds differ from the antimony halide analogues where the arene is usually acentrically bonded. 

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