Carboxyl group definition

The name, maleic anhydride, came about in the same fashion. as any number of compounds early in the petrochemical Business Many organic acids and their derivatives were given common names based on some early observations, their special source in nature, or on some special feature of their structure. MA was first isolated in the 1850—75 era by dehydration of malic acid, a sugar acid found in apple juice. The Latin word for apple is malum. Hence, malum, malic, maleic. The suffix, anhydride, which follows each alias of MA, has a simple definition a compound derived by the loss of a molecule of water from two carboxyl groups (-COOH). 

In conclusion, even though there is the definite correlation between carboxylic group index and minimum in respect to graftability in our system, a detailed work with model compounds would be required to futher elucidate the mechanism of lignin participation in the copolymerization reaction. 

A considerable difference has been observed between the spectrum of cyclohexyl and that of the cyclopentyl radical, the former exhibiting a pronounced shoulder at 250 nm with e = 920 m -1 cm-1. Cyclohexenyl and cyclopentenyl radicals show a much stronger absorption with definite maxima at 240 nm. These are allyl type radicals and like the allyl radical itself they show extinction coefficients of 7000-9000 M -1 cm-1. The optical spectrum of the allyl radical is greatly affected by unsaturated substituents which conjugate with the allylic 1 and 3 positions. These positions bear all the spin density and their interaction with carboxyl groups, for example, shifts max to 270 nm with extinction coefficients of 20,000-40,000 M 1 cm 1 (Neta and Schuler, 1975). A carboxyl group attached to the central carbon of allyl has only a minimal effect on the absorption. 

An acid is a compound capable of donating a proton to another compound (this is the so-called Br0nsted definition). The substance CH3COOH is an acid, acetic acid. However, because the dissociation of all the carboxyl groups is not complete when acetic acid is dissolved in water, acetic acid is referred to as a weak acid. The dissociation reaction for any weak acid of type HA in water is... 

Figure 6.16 Definition of syn and anti directions in the carboxylate group.

Many investigators have attempted to isolate mercury derivatives from aceto-acetie ester, but the results have been so varied that no reliance can be placed on any of the early work on this compound. Kharasch and Staveley, however, have obtained definite results by heating mercury salts of substituted acetic acids in vacuo, e.g, di-method and diethyl aceto-acetic acids when dried and heated in vacuo at 90 C. evolve carbon dioxide, and the mercury becomes bound to the carbon atoms which were formerly attached to the carboxyl groups —... 

By definition, a fatty acid is a carboxylic acid that contains twelve or more carbons terminating in a carboxyl group. Because carboxyl groups disassociate at pH above 4-5, free fatty acids occur as negative carboxylate anions (R—COO ) in seawater and marine sediments. Although fatty acid salts are more water-soluble than hydrocarbons. 

Indium(m) carboxylates In(RCOO)3 (R= H, Me, Et, Pr", Pr, or Bu ) have been prepared from metallic In or InMe3 and the anhydrous carboxylic acid. The i.r. spectra show that the carboxylate groups could be either chelating or bridging, but no definite conclusion concerning the structure or the C.N. of the In could be reached.562... 

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