Indium complex compounds

Coordination Compounds. A large number of indium complexes with nitrogen ligands have been isolated, particularly where Ir is in the +3 oxidation state. Examples of ammine complexes include pr(NH3)3] " [24669-15-6], prCl(NH3)] " [29589-09-1], and / j -pr(03SCF3)2(en)2]" [90065-94-4], Compounds of A/-heterocychc ligands include trans- [xCX py)][ [24952-67-8], Pr(bipy)3] " [16788-86-6], and an unusual C-metalated bipyridine complex, Pr(bipy)2(C, N-bipy)] [87137-18-6]. Isolation of this latter complex produced some confusion regarding the chemical and physical properties of Pr(bipy)3]3+ (167). 

Consequently, due to preferred cis-cis orientation a dimeric structure is observed for the indium complex and an unprecedented cis-trans arrangement in the thallium structure leads to a polymeric aggregate. Further N-NMR spectroscopic studies show that the aluminum and gallium complexes are stable contact ion pairs even in solution whereas the indium and thallium compounds are solvent-separated ion pairs in THE solution. 

Transformations of (Organo)silicon Compounds Catalyzed by Indium Complexes... 

The chemistry of indium complexes of aU types in metal oxidation states lower than +3 has been comprehensively reviewed. Few lower oxidation state mononuclear amido complexes of indium are well characterized, however, and no structure has been reported for an In(I) amide. The compound In N(SiMe3)2 n. which is unstable, " has been characterized NMR spectroscopy but its structure is unknown. The structures of several In(I) complexes, related to amides but outside our current scope, have been described. Like its aluminium and gallium counterparts, the p-diketuninate derivative [ In N(Dipp)C(Me) 2CH] has been characterized, as has the closely related species [ In N(Dipp)C(CF3) 2CH]. ° These feature V-shaped, two-coordination at the metal. The less bulky [(In N(Mes)C(Me) 2-CH)2] ° and 15-2.6-.Vlc,)( (Me) i are dimeric with long In In bonds of... 

The diketonates of indium(III) are thermodynamically stable complexes in non-aqueous solution,9 and are sufficiently robust to allow studies of polarographic reduction, which has demonstrated one-electron reduction to the formally indium(II) and indium(I) compounds (see Section 25.2.3.3).30... 

The molecular structure of decabenzylferrocene also helped to explain the rather low solubility of this compound in toluene or benzene, in sharp contrast with the previously found excellent solubility properties of other decabenzylmetallocenes and the pentabenzyl-Cp thallium and indium complexes in these solvents. The steric crowding of the benzyl groups in the ferrocene and their limited mobility leave little space for the solvent arene molecules to interact and subsequently to dissolve the molecule. This is quite similar to the situation encountered in the pentaphenylcyclopenta-dienyl derivatives with their closely packed phenyl rings (see Fig. 3). 

Most of the divalent indium compounds appear in the dimeric form, which involves an indium-indium bonded species or R4hi2. The structure of the indium (11) hahdes has been identified, in which the divalent ln + ions is present in the dimeric species [hi2X6] A special highlight is the compound R4lu2 (R = CH(SiMc3)2, SiBu 3, SiBu 2Ph), which has a remarkable reactivity and is used in the preparation of various indium complexes including indium cluster compounds. ... 

Most of the reported intermetallic indium complexes are those where the indium is in low oxidation state and are hence discussed in Section 8. Examples where the indium metal center is in higher oxidation states are given below. The intermetallic (dialkylaminomethyl)-phenylindium derivative is synthesized via metathesis as outlined in Scheme 17. The compound exists as a distorted trigonal bipyramid since the N In N angle of 143.1(2) falls considerably short of an ideal trigonal bipyramid (180°). 

The treatment of neutral In(SePh)3 with [PPh4]Br also results in a selenolate adduct compound [PPh4][BrIn(SePh)3]. A copper-indium complex with bridging selenolates (Ph3P)2Cu[In(/i-SeEt)2(SeEt)2] was also reported. The action of selenium on [HB(3,5-(t-Bu)2Pz)3]In or [(t-Bu3Si)2ln]2 affords [HB(3,5-(t-Bu)2Pz)3]InSe or (t-Bu3SiIn)4Sc4 (45), respectively. The tellurium does not react with [HB(3,5-(t-Bu)2Pz)3]In. ... 

Indium(I) complexes of Se and Te donors are known. The reaction between InCl and (Me3Si)3SiELi(THF)2 (E = Se or Te) and InCl leads to the metathesis product (Me3Si)3SiEIn. Chalcogenolysis with Cpin also affords the same In(I) selenolate or tellurolate. These indium(I) compounds are light-sensitive compounds. No solid-state structural data are available. 

The distribution and excretion of indium in animals depends greatly on the chemical composition of the indium compound, as well as the route of administration. For example, indium citrate was administered to animals by several routes such as subcutaneous, intramuscular, and intravenous injection (Browning 1969). For subcutaneous injection, the distribution was more uniform, but for intravenous injection, the concentration of indium was highest in the kidneys and liver. Ionic forms of indium are mostly accumulated by the kidney and excreted via the urine, while colloidal indium complexes accumulate in the liver and reticuloendothelial system and are eliminated primarily through the feces (Castro-novo and Wagner 1971). 

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