Tris complexes indium

Preparations of tris-bipyridyl (156, 519) and tris-phenanthroline indium(III) complexes have been described. The d<- d bands fall in the region of the ligand tt <-> tt transitions. The luminescence spectra of the cations are considered to arise from n d transitions (739). Cis-[Ir(phen)2Cl2]Cl is known (156) and has been resolved (104). However, the complex originally claimed as irans-[Ir(phen).2Cl2]Cl-3H20 (156) and shown to react with hydrochloric acid (452) is, in fact, (phen H+)[Ir(phen)Cl4] (104). The compounds [Ir(phen)2X.2]+ [Ir(phen)X4] are known (X = Cl, Br, or I) and the cations probably have cis configurations. 

The most stable oxo-complexes are chelate compounds. Gallium and indium form tris- -diketone complexes, soluble in alcohol and benzene, and structurally similar to those of aluminium (Fig. 155). Gallium and thallium form trioxalato compounds like the oxalato-aluminates MJ[Ga ( 304)3]HgO. All the metals form tris-complexes with oxine (Fig. 156). 

Tris(benzeneselenolato)indium(III) is an air-stable yellow microcrystalline solid, mp 150°, soluble in donor solvents and in hot aromatic solvents. It is a Lewis acid." The HNMR spectrum di(methyl-d3 sulfoxide) consists of a complex multiplet, 6.6-7.2 ppm from Me, Si. 

TRIS(0-ETHYL DITHIOCARBONATO) COMPLEXES OF TRIPOSITIVE CHROMIUM, INDIUM, AND COBALT... 

Methods for the preparation of tris(0-ethyl dithiocarbonato) complexes of chromium(III), indium(III), and cobalt(III) are presented and serve to illustrate procedures applicable to the preparation of O-alkyl dithiocarbonato, alkyl trithiocarbonato, iV,A7-dialkyldithiocarbamato, and 0,0 -dialkyl dithiophosphato complexes of several metals. 

The colorless tris(0-ethyl dithiocarbonato)arsenic(III) and yellow antimony(III) complexes have been prepared from the corresponding metal trichlorides using this procedure. Tris-(alkyl trithiocarbonato)-, tris(0,0 -dialkyldithiophosphato)-, and other tris(0-alkyl dithiocarbonato)indium(III) complexes can undoubtedly be prepared from the potassium or sodium derivatives of the ligands using this procedure. 

Tris(0-ethyl dithiocarbonato)chromium(III) is obtained as a dark blue crystalline powder which decomposes at 100 to 140°. The indium(III) ethylxanthate complex forms small colorless crystals which decompose at 130 to 150°.16,17 The cobalt (III) ethylxanthate complex is isolated as a dark green crystalline powder whose decomposition temperature determined by use of a thermal balance is 135 to 137° (lit. value, 117° 2 118 to 119°8). These compounds decompose slowly in air and more rapidly when heated in solution. The tripositive chromium, indium, and cobalt complexes are insoluble in water but are soluble in many organic solvents (Table T). 

TABLE I Solubilities of Tris(0-ethyl dithiocarbonato) Complexes of Chromium(III), Indium(III), and Cobalt(III) in Organic Solvents at 25°... 

X-ray powder diagrams obtained by the Guinier method show the tris (O-ethyl dithiocarbonato) complexes of chro-mium(III), indium(III), cobalt(III), iron(III), arsenic(III), and antimony(III) to be isomorphous. Carrai and Gottardi have determined the structure of the arsenic(III)18 and anti-mony(III)19 complexes. Crystallographic data for the cobalt(III) and chromium(III) ethylxanthate complexes are given by Derenzini20 and Franzini and Schiaffino,21 respectively. 

There is a large temperature variation of solubility for the tris-dmpp complex of indium (143) but a much smaller variation for tris(malto-lato)aluminum (242) in aqueous solution. The solubility of the former increases by a factor of 3.5, of the latter by only 1.3 times, on raising the temperature from 298 to 310 K, i.e., from the standard 25°C to the physiological 37°C. The enthalpy of solution of Al(malt)3 in water is 23kJmol , but is medium-dependent, rising to 56kJmol in 80% methanol. 

Gao, B. Wen, Y. Yang, Z. Huang, X. Liu, X. Feng X. (2008) Asymmetric ring opening of meso-Epoxides with aromatic amines catalyzed by a new proline-based N,N -dioxide-indium tris (triflate) complex,/t/v. Synth. Catal, 350 385- 390. 

For rearrangement reactions of the kinetically fast variety, i.e., for complexes which are stereochemically nonrigid, DNMR techniques have in several cases permitted detailed mechanistic conclusions via the observation of site interchanges.s-8 The first experiments were carried out by Fay and Piper15 on tris(trifluoroacetylacetona-to) complexes of aluminum(III), gallium(III) and indium(III), 3, using 19 F DNMR. These complexes which are members of the class of octahedral tris chelates M(A—B)3... 

Garbometallation of carbon-carbon unsaturated bonds is an important synthetic method for the construction of complex molecules.277-281 An example of carboindation is described with tri(5-hexenyl)indium, prepared from di(5-hexenyl)mercury and indium metal, which is cyclized to a cyclopentylindium compound.282... 

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