P-Hydroxy benzoic acid methyl ester

The opposite can be observed with acidic analytes as shown in Figure 2.18. Here, with classical RP and methanol at pH 3 the best selectivity and peak shapes were observed. On the other hand, with the shielded phases, acetonitrile gives the best separation. As already discussed, with shield phases the retention of nonpolar components (here peak 6 dimethyl phthalate) is reduced, whereas that of phenolic components (e.g., peak 5 p-hydroxy benzoic acid methyl ester) is increased. 

New Orthoform m-Amine p-hydroxy benzoic acid, methyl ester... 

The aliphatic-aromatic diacid monomers were prepared from the reaction of bromoalkanoic acid methyl ester and p-hydroxy benzoic acid methyl ester. The polymers of carboxyphenoxy alkanoic add of n = 3, 5, and 7 methylenes were soluble in chlorinated hydrocarbons and melted at temperatures below 100 °C. Copolymers of these monomers melted at lower temperatures than the respective homopolymers. These polymers displayed zero-order hydrolytic degradation profile ranging from 2 to 10 weeks. Increasing the length of the alkanoic chain, decreased the degradation rate of the polymer (Fig. 3). 

The migration of methyl to sulphur observed in reactions of o-mercapto-benzoic acid methyl ester with primary aliphatic amines, possibly via an S i mechanism, contributes another example to an extensive list of interactions of aromatic or/Ao-substituents. More conventional nucleophilic substitution processes include syntheses of L-selenomethionine, MeSeCH2 -CHa CH(NH2) C02H, and its c-ethyl and S e-benzyl analogues by treatment of O-toIuene-p-sulphonyl-L-homoserine with appropriate organo-selenium nucleophiles also, analogous reactions of hydroxy-acid... 

The coefficient of variation for the methyl and propyl esters of p-hydroxy benzoic acid were 3.2% (13 determinations) and 4.8% (14 determinations). 

Esters.— The simplest class of compounds present in essential oils are the esters or ethereal salts (p. 140). In our early discussion of these compounds in the aliphatic series it was stated that the odor and flavor of common fruits is probably due to ester compounds and that certain empirical mixtures of esters are used as artificial fruit essences. Artificial apple essence, for example, may be prepared by mixing certain proportions of ethyl nitrite, ethyl acetate and amyl valerate with chloroform, aldehyde and alcohol. An example of an essential oil which consists of a single ester is oil of wintergreen. vAdxh is the methyl ester of salicylic acid, ortho-hydroxy benzoic acid (p. 714). 

SYNS BENZOIC ACID, 2-HYDROXY-, 4-METHYL-PHENYL ESTER (9CI) p-CRESYL SAUCYLATE 4-METHYLPHENYL 2-HYDROXYBENZOATE 4-METHYLPHENYL SALICYLATE SAUCYUC ACID. p-TOLYL ESTER... 

The effect of the degree d xrlarization of the ester linkages in low-motecular-weight esters on their reactivity has been examined by studying the reaction of alcoholysis, with ceUulose, of methyl esters of benzoic, p-chloro-, p-hydroxy, p-hydroxy-, p- and o-nitrobenzoic acids, and those of phenyl-, phenoxy-, 2,4-dichlorophenoxy- and monodiloro-acetic adds. The trans-esterification reaction was carried out in non-aqueous dinrethylformamide in the presence of catalysts (sodium methylate, cadmium acetate, p-toluenesulphonic add) at 110-140° C. 

CAS 94-18-8 EINECS/ELINCS 202-311-9 Synonyms Benzoic acid, 4-hydroxy-, phenyl methyl ester Benzyl 4-hydroxybenzoate Benzyl p-hydroxybenzoate Phenylmethyl 4-hydroxybenzoate Definition Ester of benzyl alcohol and p-hydroxybenzoic acid Empirical C14H12O3 Toxicology TSCA listed Uses Preservative, bactericide, fungicide for foods, pharmaceuticals, industrial applies. antimicrobial in cosmetics Regulatory BP compliance Manuf./Distrib. Aldrich http //www.sigma-aldrich.com-, Alfa Aesar http //www.aifa.com-, Archimica Inc http //www.archimica.com-. 

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