Benzene polycarboxylate

Metal organic frameworks formed using benzene polycarboxylates have been extensively studied and have revealed some very interesting properties. 

There is an interesting technique which makes it possible to introduce carboxylic acid groups into a copper phthalocyanine structure by an economical route. Carrying out the phthalic anhydride/urea process in the presence of a small amount of trimellitic acid or another benzene polycarboxylic acid will afford a car-boxylated pigment. 

Only a few systematic studies have been carried out on the mechanism of interaction of organic surfactants and macromolecules. Mishra et al. (12) studied the effect of sulfonates (dodecyl), carboxylic acids (oleic and tridecanoic), and amines (dodecyl and dodecyltrimethyl) on the electrophoretic mobility of hydroxyapatite. Vogel et al. (13) studied the release of phosphate and calcium ions during the adsorption of benzene polycarboxylic acids onto apatite. Jurlaanse et al.(14) also observed a similar release of calcium and phosphate ions during the adsorption of polypeptides on dental enamel. Adsorption of polyphosphonate on hydroxyapatite and the associated release of phosphate ions was investigated by Rawls et al. (15). They found that phosphate ions were released into solution in amounts exceeding the quantity of phosphonate adsorbed. 

Also, when benzene polycarboxylic acid compounds (31-35) were used, a 3 1 complex (39) of trimellitic acid (34) with 1, and a 2 1 complex (40) of pyromel-litic acid (35) with 1 were obtained (Table 4). Although the inclusion complexes were not obtained with the other similarly structured compounds (31-33), it was shown that as the number of carboxyl groups of the host increases, the inclusion complexation becomes easier. 

In a stndy of retention of aromatic carboxylic acids under IPC conditions, linear free energy relationships were observed between the capacity factors and the extraction eqnilibrinm constants of benzoic acid and naphthalene carboxylic acid. The capacity factor of benzene polycarboxylic acids was directly related to then-association constants and qnatemary ammonium ions calculated on the basis of an electrostatic interaction model [27,28],... 

Irradiation of (Z)-cyclooctene in the presence of a triplet sensitizer, such as xylene (Et 337 kJ mol J), affords the E-isomer, although in a very low chemical yield.582 In contrast, the singlet state sensitized isomerization by benzene polycarboxylate derivatives (Es 420 kJ mol leads to (E)-cyclooctene in up to 26% chemical yield (Scheme 6.11).583... 

Bemis, A.G., Dindorf, J.A., Horwood, B., Samans, C. Phthalic Adds and other Benzene-polycarboxylic Acids In KJrk-Othmer, Encycl. Chem. Tech., 3.Ed., 17, 732 (1982)... 

Scheme 1. Some extensively used benzene-polycarboxyl-ate anionic ligands.

This example emphasizes the potentiality of the benzene polycarboxylate ligands. However some other coordination polymers containing transition metal ions deserve to be highlighted. 

List of lanthanide based coordination polymers with benzene polycarboxylate ligands. Only structurally characterized... 

Scheme 2.2 Examples of types of ligands (or their precursors) in metal catalysts for the peroxidative oxidation of alkanes (a) C-based scorpionates, (b) azoderivatives or arylhydrazones of /S-diketones, (c) aminopolyalcohols, and (d) benzene polycarboxylic acids.

R (C4He)xC02H + (Me6HC%N)3P0 - cat. effect, polymerization mechanism (2206). Y(C02H)n - (Bu3Sn02C)nY aliphatic dicarboxylic acids (I515. I765, 1793, 2966), benzene polycarboxylic acids (572, 1795, 2619). 

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