Indium complexes iodides

Reaction with Propargyl Halides. The indium-mediated coupling of propargyl bromide with a variety of imines and imine oxides afforded homo-propargylamine derivatives in aqueous media under mild conditions.78 Propargylation of glyoxylic oxime ether in the presence of a catalytic amount of palladium(O) complex and indium(I) iodide in aqueous media was also studied (Eq.11.47).79... 

A mixed indium hydride halide complex, (l) InH2Cl (29) has been prepared from the 1 1 reaction of [InH2Cl(NMe3) ] with carbene (1) (R = Mes, R = H), as shown in Scheme iP The structure of (29) is monomeric with the geometry at the In center close to tetrahedral. The In-C distance (2.244(6) A) is similar to those observed in (28) (2.200(7) A) and (25) (2.253(5) A). A related mixed gallium hydride iodide complex (1) GaH2l (30) has been isolated from the reaction of (26) with GaT, with concomitant deposition of galhum metal. Complex (30) is isostructural with the related indium complex (29) and has a Ga-C bond distance of 2.022(4) A. 

In the past decade much effort in organoindium chemistry has been devoted to study of carbonyl allylation and aUylindation of carbon-carbon multiple bonds with allylic indium reagents. Apart from the conventional transmetalation of allyl-lifhium or aUyl Grignard reagents with indium(III) halides, a method widely used for preparation of allyhndium(III) compounds is the oxidative addition of metallic indium or indium(I) iodide to aUyhc substrates [3, 6]. Transmetalation of allylstan-nane with indium(III) chloride also gives allylindium(III) [7]. Allylindium(I) was recently prepared by transmetalation of allylmercury with metallic indium in water this compound is regarded as an intermediate in the allylation of carbonyl compounds in aqueous media [8]. A new method of preparation of allylic in-dium(III) reagents - reductive transmetalation of a 7r-allylpalladium(ll) complex with indium(I) salts has been reported this enables the use of a wide variety of allylic compounds and solvents [9]. 

The largest well-defined oligomer of this type is currently the linear hexa-indium complex, 21 (Fig. 8), supported by a single ortho- y y substituted P-diketiminate ligand at each four-coordinate In centre and terminated by two iodide substituents to maintain charge balance [200]. Compound 21 displayed an absorption maximum in hexane at ca. 349 nm, which was interpreted as evidence for the existence of electronic delocalisation across the indium a framework analogous to that observed in isoelectronic catenated group 14 systems. 

The effect of metal promoter species on the rate of carbonylation of [Ir(CO)2l3Me] was tested. Neutral ruthenium iodocarbonyl complexes such as [Ru(CO)3l2]2> [Ru(CO)4l2] or [Ru(CO)2l2]n were found to give substantial rate enhancements (by factors of 15-20 for a Ru Ir ratio of 1 13 at 93 °C, PhCl). Indium and gallium triiodides and zinc diiodide had comparable promotional effects. By contrast, addition of anionic ruthenium(II) species [Ru(CO)3I3] or [Ru(CO)2I4]2 did not lead to any appreciable promotion or inhibition. This behaviour indicates that the ability to accept an iodide ligand is a key property of the promoter. Indeed, it has been demonstrated that an iodide ligand can be transferred from [ Ir(C0)2l3Me] to neutral ruthenium or indium species [73,74],... 

Two classes of promoter have been identified for iridium catalysed carbonylation (i) transition metal carbonyls or halocarbonyls (ri) simple group 12 and 13 iodides. Increased rates of catalysis are achieved on addition of 1-10 mole equivalents (per Ir) of the promoter. An example from each class was chosen for spectroscopic study. An Inis promoter provides a relatively simple system since the main group metal does not tend to form carbonyl complexes which can interfere with the observation of iridium species by IR. In situ HP IR studies showed that an indium promoter (Inl3 Ir = 2 1) did not greatly affect the iridium speciation, with [MeIr(CO)2l3] being converted into [Ir(CO)2l4] as the batch reaction progressed, as in the absence of promoter. 

Vinyl halides add to allylic amines in the presence of Ni(cod)2 where cod=l, 5-cyclooctodine, followed by reduction with sodium borohydride. Aryl iodides add to alkynes using a platinum complex in conjunction with a palladium catalyst. A palladium catalyst has been used alone for the same purpose, and the intramolecular addition of a arene to an aUcene was accomplished with a palladium or a GaCl3 catalyst, " AUcyl iodides add intramolecularly to aUcenes with a titanium catalyst, or to alkynes using indium metal and additives. The latter cyclization of aryl iodides to alkenes was accomplished with indium and iodine or with Sml2. " ... 

Among the methods for the separation of small amounts of indium before its determination, the solvent extraction methods in general, and extraction of indium-iodide and -bromide complexes in particular, are of the utmost importance. 

The indium iodide complex [1-3] is > 99% extracted into diethyl ether from 0.5-2.5 M HI (6-30%). Gallium is not extracted under these conditions, but it is extracted from 6 M HCl. The hydriodic acid can be replaced by 0.5-3 M H2SO4 containing 15-20% of Kl. Chloride, bromide, fluoride, phosphate, and citrate do not interfere in the extraction of In from iodide media. Under the optimum conditions for the extraction, Tl, Cd, and Sn (and some Bi, Zn, Hg, and Sb) are extracted. Aluminium and Fe(II), like Ga, are not extracted. The indium iodide complex has also been extracted into chloroform containing N-benzylaniline [4,5]. 

The indium bromide complex [6,7] can be extracted into diethyl ether from 4.5-5.5 M HBr (-40%). When extraction with DIPE is applied, the concentration of HBr should be -6 M. The selectivity of In extraction from a bromide medium is lower than that from iodide solutions. Ga, Fe(III), Sb(V), Au(III), Tl(III), Sn, and Mo are extracted with indium. Indium can be stripped with water from the ether extract. 

To determine indium in mineral concentrates (containing -0.1% of In), the following procedure has been recommended A weighed sample (0.1-1 g) is decomposed in a mixture of HCl and HNO3, tin is expelled as SnBr4, and Pb is precipitated as PbS04. The hydroxides of metals which, like indium, form sparingly soluble hydroxides, are then twice precipitated with an excess of ammonia. After the precipitated hydroxides have been dissolved in hydrochloric acid, potassium iodide is added, indium is extracted as the iodide complex into diethyl ether, and then stripped into aqueous solution and determined spectrophotometrically with PAR [23],... 

Beryllium, Ga, Al, Fe(III), and V(IV) interfere in the determination of In as a complex with ECR and CTA. The influence of Zr, Th and U is smaller. Anions complexing indium, viz. EDTA, citrate and tartrate, must be absent. This method for determining indium becomes highly selective when indium is first separated as the iodide complex (see Section 24.2.1). 

Cooper et al. reported that the cascade reaction of the palladium-catalyzed cyclization and the Barbier-type allylation of the 1,3-diene-aryl iodide 514, the aldehydes 515, and indium gave the heterocycles 516 in good yields (Scheme 154).220b The reaction proceeds through oxidative addition of a C—I bond of 514 to Pd(0) and subsequent insertion of a double bond of 517 to give the jr-allylpalladium intermediate 518. Transmetalation of the jr-allylpalladium 518 with indium leads to the allylindium complex 519, and the following reaction with the aldehydes 515 gives 516. 

Barium iodate 1-hydrate, synthesis 4 Indium(I) bromide, synthesis 6 Hexachlorodisiloxane, synthesis 7 Trichlorosilanethiol, synthesis 8 Tris(acetylacetonato)silicon chloride, synthesis 9 Titanium(III)chloride, synthesis 11 Bis[tris(acetylacetonato)titanium(IV)] hexachloro-titanate(IV), synthesis 12 Zirconium(IV) iodide, synthesis 13 (Triphenyl) aminophosphonium chloride, synthesis 19 (Dimethylamido)phosphoryl dichloride, synthesis 20 Bis(dimethylamido)phosphoryl chloride, synthesis 21 Trimeric and tetrameric phosphonitrilic bromides, synthesis 23 Phosphorus(V) chloride-boron trichloride complex, synthesis 24... 

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