Phthalic acid structure

Phosphine(s), chirality of, 314 Phosphite, DNA synthesis and, 1115 oxidation of, 1116 Phospholipid, 1066-1067 classification of, 1066 Phosphopantetheine, coenzyme A from. 817 structure of, 1127 Phosphoramidite, DNA synthesis and, 1115 Phosphoranc, 720 Phosphoric acid, pKa of, 51 Phosphoric acid anhydride, 1127 Phosphorus, hybridization of, 20 Phosphorus oxychloride, alcohol dehydration with. 620-622 Phosphorus tribromide, reaction with alcohols. 344. 618 Photochemical reaction, 1181 Photolithography, 505-506 resists for, 505-506 Photon, 419 energy- of. 420 Photosynthesis, 973-974 Phthalic acid, structure of, 753 Phthalimide, Gabriel amine synthesis and, 929... 

The amidic polyols derived from bis (diethanolamide) of phthalic acid (structure 19.6) have the same functionality as o-TDA based polyols and have internal ethylene oxide (EO), similar to commercial o-TDA polyether polyols. The difference is that the labile amino groups are replaced with more stable amidic groups and the amidic polyol does not have a methyl group in the aromatic nucleus. The similarities between o-TDA based polyols and the amidic polyols derived from bis (diethanolamide) of phthalic acid are shown in the structures presented in Figure 19.1. 

P represents shaded portion of phthalic acid structure... 

It is, however, possible to produce other structures. For example, if phthalic acid is condensed with glycerol, the glycerol will react at each point (Figure 2.9). 

This will lead initially to branched chain structures such as indicated schematically in Figure 2.10, G indicating a glycerol residue and P a phthalic acid residue. In due course these branched molecules will join up, leading to a cross-linked three-dimensional product. 

These resins are produeed by reacting a polyhydric alcohol, usually glycerol, with a polybasic acid, usually phthalic acid and the fatty acids of various oils such as linseed oil, soya bean oil and tung oil. These oils are triglycerides of the type shown in Figure 25.30. R], R2 and R3 usually contain unsaturated groupings. The alkyd resins would thus have structural units, such as is shown in Figure 25.31. 

It is prepared by reaction of ethylene glycol with 1,4-benzenedicarboxylic acid (tere-phthalic acid). Draw the structure of PET. 

The formation of phthalocyanines can be formally regarded as cyclotetramerization of the appropriate substituted or unsubstituted derivatives of phthalic acid. It should be emphasized that mixtures of structural isomers are obtained if these derivatives are substituted as follows ... 

Tractable polymers can be prepared when amino and anhydride functions are not located on the same aromatic ring, and different strategies were employed to obtain soluble polymer. AB benzhydrol imide was prepared by polycondensation of 4-(3-amino-l-hydroxymethylene) phtlialic acid monomethyl ester in NMP. The polymer soluble in NMP has been used as adhesive and coating.56 A second approach was based on an ether imide structure. AB aminophenylether phthalic acids (Fig. 5.34) were prepared by a multistep synthesis from bisphenols.155 The products are stable as hydrochloride, and the polycondensation takes place by activation with triphenylphosphite. The polymers are soluble in an aprotic polar... 

There are numerous possible monomers that can be used in the backbone of the polyester prepolymer. However, typical monomers are 1,2-propanediol, as just mentioned, with maleic acid (usually added as the anhydride) to provide the sites of unsaturation, and phthalic acid (again usually added as the anhydride) to act as the second of the two diacid species. The structures of these latter two substances are shown in Figure 4.1. 

Figure 4.1 Structures of (a) maleic acid and (b) phthalic acid...

Nonlinear polymers are obtained from monomers at least some of which possess a functionality exceeding two. In other words, nonlinear polymers may be defined as those containing units some of which are yolyfunctional, this term being reserved for functionalities exceeding two. Thus, the condensation of glycerol, a trifunctional reactant, with phthalic acid, a bifunctional reactant, yields a nonlinear polymer comprising structures such as... 

Ejlertsson J, Alnervik M, Jonsson S, Svensson BH (1997) Influence of water solubility, side-chain structure on the degradation of phthalic acid esters under methanogenic conditions. Environ Sci Technol 31 2761-2764... 

However, the formation of these products does not appear to play a critical role in the decision as to whether the 425 nm and 480 nm maxima are due to different states of the same molecule or to different compounds. It was reported that special care was taken to ensure the purity of luminol and of 3-aminophthalate 109>. In commercially available 3-amino-phthalic acid a yellowish impurity exhibiting brilliant green fluorescence was detected 109> this substance also formed in neutral solutions of pure 3-amino phthalic acid and crystallized from these solutions in yellow crystals. The structure of this substance was determined to be 53 its absorption spectrum has a maximum at 388 nm the fluorescence maximum is at 475 nm, with a fluorescence quantum yield of about 0.75 in DMF i 9). 

FIGURE 5.8 The molecular structures of phthalic acid and potassium hydrogen phthalate (KHP). 

For standardizing a base solution, primary standard grade potassium biphthalate is a popular choice. Also called potassium hydrogen phthalate, potassium acid phthalate, or simply KHP, it is the salt representing partially neutralized phthalic acid and is a monoprotic weak acid. The true formula is KHC8H404. Figure 5.8 shows the chemical structure of phthalic acid and KHP. The reaction with a base is as follows ... 

Table 3 presents the experimental enthalpies of formation of polynitrobenzenes and Table 4 presents the calculated additivity values and DSEs for these same compounds. Enthalpy-of-formation values have been determined experimentally for all three dinitrobenzene isomers in the gaseous state. The enthalpy-of-formation difference between the meta and para isomers is indistinguishable from 0. Conventional wisdom suggests that the para isomer should be destabilized relative to the meta because of adjacent positive charges in key ionic or polar resonance structures. Thus it seems that electronic effects due to meta/para dinitro substituent position are small. This small enthalpy-of-formation difference is similar to that for the meta and para dicyano, difluoro and dichloro benzenes, but does not mimic the ca 22 kJ mol 1 difference for the phthalic acids with which the... 

The direct reaction of [TCO4] in ethanolic solution with dppe and oxalic acid produces the red Tc" complex [Tc(ox)(dppe)2] (552). Attempts to prepare similar complexes with succinic acid, phthalic acid, or salicylic acid failed, or the complexes were stable in solution only. " Similarly, cationic complexes of Tc" are produced by reaction of the versatile precursor [TcO(OH)(dppe)2] (204) with various dithiocarbamates, which produces several complexes of general formula [Tc(dtc)(dppe)2] (553). For this reaction the reductant formamidine sulphinic acid (510) was required in an alkaline solution. The X-ray crystal structure of [Tc(S2CNMe2)(dppe)2] (554) shows a distorted octahedral geometry. Cyclic voltammetry reveals a reversible reduction wave Tc"/Tc couple at —0.53 V, and a reversible oxidation at +0.3 V for the Tc" /Tc" couple. The same compound (554) was also prepared from the thiourea precursor [TcO(tmtu)4] + (91).The reaction of this precursor in dmf in the presence of dppe produced a mixture of brown [TcO(dtc)(tmtu)2] and the Tc" complex (553). The first compound is probably an intermediate... 

Monomer structure can affect the competition between cyclization and linear polymerization. For example, phthalic acid (ortho isomer) is more prone to cyclization than terephthalic acid (para isomer) at the very-low-molecular-weight end, for example, the dimer stage. The ortho structure makes more likely the conformations that are more favorable for cyclization. Stiff linear chains such as those formed in the reaction between an aromatic diamine and aromatic diacid chloride are much less prone to cyclization than the flexible chains formed from the corresponding aliphatic monomers. 

Young male Wistar rats were given 2000 mg/kg bw di(2-ethylhexyl) phthalate per day by gavage for periods of 3-21 days (Lake et al, 1975). Treatment caused increases in relative liver weight and in microsomal cytochrome P450 content. Ultra-structural examination revealed marked peroxisome proliferation and a dilation of the smooth and rough endoplasmic reticulum. Rats were also treated with mono(2-ethyl-hexyl) phthalate, 2-ethylhexanol and phthalic acid at doses equimolar to 2000 mg/kg bw per day di(2-ethylhexyl) phthalate for seven days. While phthalic acid had no effect, both mono(2-ethylhexyl) phthalate and 2-ethylhexanol increased relative liver weight and produced hepatic peroxisome proliferation. 

Benzoic acid [65-85-0], C6H5COOH, the simplest member of the aromatic carboxylic acid family, was first described in 1618 by a French physician, but it was not until 1832 that its structure was determined by Wnfiler and Liebig. In the nineteenth century benzoic acid was used extensively as a medicinal substance and was prepared from gum benzoin. Benzoic acid was first produced synthetically by the hydrolysis of benzotrichloride. Various other processes such as the nitric acid oxidation of toluene were used until the 1930s when the decarboxylation of phthalic acid became the dominant commercial process. During World War II in Germany the batchwise liquid-phase air oxidation of toluene became an important process. 

Another effect of the nature of phthalic acid concerns the activation volume, Vo. The results reported in Fig. 89 show that, independently of the lactam-12 content, the replacement of iso- by fere-phthalic unit leads to higher values of V0, whatever the temperature. This conclusion remains valid if Vo values are compared as a function of (T - Ta), in order to take into account the chemical structure dependence of Ta (Table 8). 

Phthalates are the esters of phthalic acid having the following general structure ... 

In some cases, network structure is modified by aminolysis reactions25. An example is the polymer formed from diglycidylic ester of o-phthalic acid and diaminodiphenilmethane. Aminolysis makes the chain between crosslinks shorter and influences the properties of the polymer (dynamic shear modulus in a rubbery... 

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