Indium carboxylates

As previously mentioned, the aluminum carboxylate derivative has been characterized in situ. The indium carboxylate complexes exhibit typical NMR spectra expected for hexa-coordinated systems. The X-ray crystal structure of In(OEP)C02CH3 2CHCI3 has been solved Figure 11 presents the ORTEP view of this complex. 

To these two sets of results we can contrast the IR spectrum reported for adsorption from several torr of acetic acid gas onto oxidized indium films. This spectrum consists of two broad peaks at 1590 and 1455 cm-1, attributed to the asymmetric and symmetric carboxylate stretch. Both peaks are of roughly similar intensity. 

The indium-mediated reaction of 2-(bromomethyl)acrylic acid with carbonyl compounds gives the corresponding 7-hydroxy-a-methylene carboxylic acids, and a-methylene-7-lactones are obtained after acidic workup (Scheme 28).80,144-146 The indium-mediated addition of 4-bromocrotonic acid to a variety of aldehydes and ketones proceeds exclusively at the ct-carbon of the carboxylic acid. The effect of solvent, including an ionic liquid, is minimal allowing a wide choice of conditions (Scheme 29).61... 

DOTA is of particular interest as a BFC for radiolabeling of small BMs with yttrium and lanthanide isotopes. The macrocyclic framework is well organized so that it forms yttrium and indium complexes with high thermodynamic stability and kinetic inertness. The pXa values of the carboxylic groups are in the range 2-5. Lower pKa values result in less competition from protons, high stability of the metal complex, and minimum acid-assisted demetallation, even... 

The carboxylates of indium and thallium are obtained by dissolving the oxides in acid. Acetate and trifluoroacetate salts are used extensively as reagents in organic synthesis. Certain other thallium compounds have been used also. The trifluoroacetate, T1(02CCF3)3, will directly thallate aromatic compounds to give arylthal-lium species, for example, C6H5T1(02CCF3)2 (cf. aromatic mercuration, Section 15-15) and oxidize arenes to biaryls. 

Methylisoxazole-5-carboxylic acid was converted into the corresponding 5-carboxamides and 5-(l/7-pyrazol-l-ylcarbonyl) derivatives in satisfactory yields by treatment with thionyl chloride and amines or pyrazoles <2002SC425>. A three-component assembly of isoxazole-5-carboxylic acid chloride, 1,1-dimethylallene, and bis-pinacolatodiboron, catalyzed by a phosphine-free palladium complex, gave 2-acylallylboronate derivatives regiose-lectively (Equation 47) <2003JA12576>. On the other hand, a mild procedure allowed the preparation of /3,7-unsaturated ketones by simple reaction of 3-aryl-5-methylisoxazole-4-carboxylic acid chlorides with allyl bromide and indium in DMF (Equation 48) <1997TL8745>. 

Carboxylic acids represent a group of readily available and relatively inexpensive extractants. They have found rather limited application in commercial processes, however, probably on account of their generally low selectivity and poor pH functionality. Nevertheless, they have been used for the separation of copper from nickel,the removal of iron from the rare-earth metals, separations among yttrium and the rare earths, 9 he recovery of indium and galliiun, the removal of... 

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