Carboxylate ions, aliphatic free

Figure 14. Free energy of binding vs. nonpolar surface areas for a series of aliphatic carboxylate ions interacting with HSA.

Changes in aliphatic side chains are mainly initiated by the abstraction of a hydrogen atom from a C-H bond. This produces a free radical which in the absence of O2 can combine with similar free radicals to give dimerization products or with CO2 [probably the CO2 ion. (40)] to give monoamino-dicarboxylic acids. In oxygen these are replaced by oxidative reactions which produce carbonyl, hydroxyl, and carboxyl groups through hydro-peroxy intermediates ... 

Complexes obtained by interactions between aliphatic amines and carboxylic acids have a structure type of the ion pair and complex composition 1 1. Their IR spectra do not have the characteristic absorption band for free yC=0 in the region from 1780 to 1700cm . However, new characteristic absorption bands appear for the carboxylate anion in 1680-1560cm (uas COO ) and 1400-1300cm (y COO ). Some additive bands also appear The vibration NH" HO (in the region 2800-2200 cm ), as in the salts in solid state, and the bands NH2" or... 

Aliphatic amines are about as basic as ammonia aromatic amines are considerably less basic. Although amines are much weaker bases than hydroxide ion or ethoxide ion, they are much stronger bases than alcohols, ethers, esters, etc. they are much stronger bases than water. Aqueous mineral acids or carboxylic acids readily convert amines into their salts aqueous hydroxide ion readily converts the salts back into the free amines. As with the carboxylic acids, we can... 

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