Indium complexes ethers

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... 

Effective catalysts include TiCL,57 SnCl4,58 (CH3)3Si03SCF3,59 and Bu2Sn03SCF3.60 61 Indium trichloride catalyzes Mukaiyama additions in aqueous solution. The reaction is best conducted by preforming the aldehyde-InCl3 complex and then adding the silyl enol ether and water. 

The described preparation of Inl is a modification of a 3-step literature procedure in which indium shot is hammered into indium foil and heated with iodine to form Inig/ The Inlg is then heated with excess indium foil to form 10314 (3 complex of Inl[lnl3]).ln a third step, the Iri2l4 is treated with diethyl ether whereupon it disproportionates to insoluble Inl and soluble Inij etherate that are separated by filtration. 

Dialkynyl ligands, in platinum(II) complexes, 8, 545 iV,iV-Diallylamine, via allyindium reagents, 9, 703-704 Diallyl clusters, in trirutheniums and triosmiums, 6, 773 gem-Diallyl esters, via indium-mediated allylation, 9, 677 Diallyl ethers, isomerization, 10, 90 Diamagnetic ylides, with gold(II), 2, 278 Diamides... 

The tendency of the aluminium atom to complete its electron octet is manifested as the Lewis acidity of organoaluminium compounds. This is demonstrated by the formation of 1 1 complexes of trialkylaluminium with anions or bases such as ethers and amines. Organoaluminium compounds are generally more acid than the organoderivatives of boron, indium and gallium. For steric reasons, complex formation is more difficult in compounds of... 

As bromide complexes, indium has been extracted with diethyl ether [68] or diisopropyl ether, and gold(III) (from 3 M HBr), also with di(2-chloroethyl) ether [69]. 

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],... 

The Mukaiyama aldol reaction involves the addition reaction of a TMS-enol ether to an aldehyde. Loh et al. have investigated the reaction of l-methoxy-2-methyl-l-trimethylsiloxypropene with aliphatic and aromatic aldehydes in chloride, [BF4] and [PFg] ionic liquids. The yields varied considerably and it was found that the chloride ionic liquids gave the best yields (50-74%) [230]. Ruthenium complexes have been used in the addition of aUyl alcohols to aldehydes and imines in [BMIM][Pp6] [231] (and later in a very similar paper [232]). The addition of a cootalyst such as indium(iii) acetate was found to dramatically improve the yields in some cases and it was foimd that the ionic Uquid/catalyst combination could be recycled. Examples of these reactions are shown in Scheme 5.2-100. 

Reaction with Allylic Halides, Alcohols, and their Derivatives. Allylation of allyl and propargyl trimethylsilyl ethers as well as benzyl and propargylic alcohol derivatives proceeds in the presence of a catalytic amount of Lewis acids, such as ZnC, TMS(OTf), and B(C6F5)3. Direct substitutions of the hydroxyl group of allylic, ben-zylic, and propargylic alcohols are catalyzed by HN(S02F)2, a rhenium-oxo complex, and InCls (eq 27). A combination of chlorodimethylsilane and allyltrimethylsilane effectively promotes the deoxygenative allylation of aromatic ketones in the presence of a catalytic amount of an indium compound, such as indium trihalide or metallic indium (eq 28). Allylation of cyclic allylic acetates with allyltrimethylsilane can be catalyzed by molecular iodine. ... 

Spec determination of indium after an ether extraction from hydrobromic acid, and benzyl alcohol extraction of its complex with bromopyrogallol red (pH 9.0) Specf = 395 nm, = 461 nm of the indium 5-Br-SASH chelate in a water-ethanol (63%) medium (pH = 4.6)... 

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