Antimony complex halides

Some other arene-antimony halide complexes have been structurally characterized all have intermolecular secondary Sb - -X interactions and supramolecular self-organization. Examples are naphthalene-2SbCl3 [414], phenanthrene-2SbCl3 [415], pyrene-2SbBr3 [416], and [(SbCl3)2(//- / -[2 ](l,4)cyclophane].v-0,5C6H6 [417], In the naphthalene complex [414] pairs of SbCl3 molecules are interconnected in planar stacks, with shorter primary bonds (axial Sb-Cl 2.367 A, equatorial Sb-Cl 2.347 A) and intermolecular distances Sb- -Cl 3.581-3.832 A. 

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 ... 

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. 

Reaction of 74 with alkyl halides gives 75 (equation 285 °). Triorganoantimony compounds containing allyl groups react with the iron complex 76 with elimination of the allyl moiety to give 77 (equation 286 ). Reaction of the tetracoordinate antimony ate complex 78 with the iron complex 79 gives 80, which has been characterized by X-ray analysis (equation 287 ). 

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. 

Photoelectron spectra for the antimony trihalides and Sb, Cl, and Br n.q.r. spectra for a number of adducts of the trichloride and bromide have been reported. The complex SbCl3,GaCl3 has been isolated, whereas a simple eutectic only is observed in the SbCl3-AlCl3 system. Antimony and bismuth halide complexes with substituted l,2-dithiol-3-thiones can be obtained, and the... 

The salts of the parent compound Cl2C=NH (IV) were synthesized by Allenstein and Schmidt ( ) in 1964, by adding hydrogen chloride to the antimony pentachloride complexes of cyanogen halides V. The compounds obtained (IV) are stable at room temperature, with the exception of the iodine derivative (IV, X=I)( ). 

Interesting examples of self-assembly are provided by the arene complexes of antimony halides (so-called Menschutkin-type complexes). The addition compound between benzene and antimony trichloride, C6H6-2SbCl3, has been known for a long time [407, 408], but its crystal structure has been determined by X-ray diffraction only recently [409], It consists of SbCls molecules r-bonded to both faces of the benzene ring, to form an inverse sandwich moiety, 164. Further secondary Sb - bonds connect these tectons into a self-organized layer structure. 

Fromherz and his colleagues began in 1927 a study of the halide complexes of the family tin(II), thallium(I), and lead(II), > > where the corresponding gaseous ions contain two s electrons. The present author has measured antimony(III), while Hume and Newman studied bismuth(III). This family became interesting to solid state physicists investigating the mixed crystals with alkali halides, and Seitz proposed, 1938, that the weaker band of T1(I) in such crystals is caused by the atomic transition Sq(6s ) —> Pi(6s6 ), while the stronger band is caused by... 

Attempts to obtain alkylcarbonium complexes by dissolving alkyl chlorides (bromides) in liquid Lewis acid halides (stannic chloride, titanium (IV) chloride, antimony pentachloride, etc.) as solvent were unsuccessful. Although stable solutions could be obtained at low temperature with, for example, t-butyl chloride, the observed N.M.R. chemical shifts were generally not larger than 0 5 p.p.m. and thus could be attributed only to weak donor-acceptor complexes, but not to the carbonium ions. The negative result of these investigations seems to indicate that either the Lewis acids used were too weak to cause sufficient ionization of the C—Cl bond, or that the solvating effect of the halides... 

Rubidium metal alloys with the other alkali metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double halide salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and zinc. These complexes are generally water insoluble and not hygroscopic. The soluble rubidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide,... 

In the halide group the most active lone pair is found in the phosphortrihalides. The stability of the boron complexes AXZ.BXZ decreases in the sequence PXj -> AsXz SbX3, no antimony compounds being observed. The halides of the sulphur group do not form compounds at all it seems improbable that the only reason for this behaviour is the disproportionation of these halides. 

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