Naming phenols

All of the above examples are acetates of active alcohols. Here, we also mention the acetate of a phenol, namely the provitamin a-tocopheryl acetate, whose natural enantiomer of absolute configuration (2R,47 ,87 ) is shown as 8.73. a-Tocopheryl acetate is a substrate of cholesterol esterase (EC 3.1.1.13), and was hydrolyzed in rats faster than its (2S,47 ,87 )-epimer. In vitro experiments required a-tocopheryl acetate to be dispersed as a micellar pseudosolution, and the nature of the bile salt used to prepare micelles had a profound effect on the substrate stereoselectivity of the reaction [95] [96], Only when the micelle composition approximated that of the gastrointestinal tract did the in vitro substrate stereoselectivity resemble that seen in vivo. 

Salicin is an (9-glycoside of a phenol, namely salicyl alcohol. Salicin is a natural antipyretic and analgesic found in willow bark, and is the template from which aspirin (acetylsalicylic acid, see Box 7.13) was developed. Prunasin from cherry laurel is an example of a cyanogenic glycoside, hydrolysis of which leads to release of toxic HCN (see Box 7.7). It is the (9-glucoside of the alcohol mandelonitrile, the trivial name for the cyanohydrin of benzaldehyde. It is the further hydrolysis of mandelonitrile that liberates HCN. 

Flavonoid Yellows Structures containing Phenols, names depending OH or OCH position Quercetin Black oak (Quercus velutina Lam.) Onions (Allium sp.) Red grapes (Vitis sp.) Requires mordant. Metal ions in a mordant fbrm insoluble lake with OH and OCH groups. 

Figure 19 displays another representative of substituted phenols, namely p-nitrophenol, whose history of discovery was mentioned in Section I. A knowledge of its structure and IR spectrum is important for the study of inter- and intra-molecular interactions via a variety of spectroscopic methods. 

Such a phenol keto-tautomer equivalent strategy was used for conjugate reduction of cyclic enones (equation 5). The quinone monoketals 9 and para-quinol ethers 10 were used as precursors to keto-tautomer equivalents of substituted phenols, namely enones 11, which were prepared by action of bis(2,6-di-fert-butyM-methylphenoxy)methylaluminium (MAD), followed by addition of lithium tri-iec-butyl borohydride (L-Selectride). The enones 11 obtained are reasonably stable at a freezer temperature without aromatization. ... 

The pioneer in the field of truly synthetic fibres was Carothers, who demonstrated that two comparatively simple compounds derived from phenol, namely, hexamethylenediamine and adipic acid, could be caused to polymerize to form a potentially fibrous polymer. This was spun into yarn which was successfully placed on the market as nylon. Shortly afterwards ethylene glycol and terephthalic acid were condensed to a polymer from which Terylene or Dacron was made. Ethylene is a by-product in the cracking of petroleum and is the starting point in the manufacture of vinyl chloride and acrlyonitrile, from which Vinyon and the various polyacrylonitrile fibres respectively are spun. 

The antioxidant system investigated is a synergistic syst composed of a phenol, namely, tetrakls[methylene 3-(3, 5 -di-t-butyl-4 -hydroxyphenyl)propionate]methane (Irgcmox 1010) and a sulfur compound, namely, dlstearylthiodipropionate (DSTDP), both added at 0.5 phr to the CPE. The dehydrochlorlnation stabilizers consisted of a bisphenol A epoxy resin (DER331) added at 4 phr concentration and PbO added at 5 phr concentration. The effects of these systems on the dehydrochlorlnation rates of peroxide crosslinked CPE and 2-roercaptoimidazoline crosslinked CPE are shown in Figure 2. 

By structural similarity to aromatic monoamines, aromatic amino acids and phenolics namely tyrosine, salicylic acid, benzoic acid and its derivatives were tested as putative substrates. Fig. 2 shows the comparison of the peptides (V -generating activities in the presence of various substrates. Reaction was initiated and assessed by adding CL A, peptide, Cu, H202 and substrates (aromatic monoamines, amino acids, or phenolics) to phosphate buffered saline in this order. The extent of CLA-chemiluminescence was expressed using the relative luminescence unit (rlu). 

Although outside the scope of the present chapter, another transformation of interest is the conversion of the fully hydrogenated product from phenol, namely cyclohexanol, to cyclohexanone in 100% yield by addition of a dichloromethane solution to bis(quinuclidine)bromine fluoroborate and silver fluoroborate in dichloromethane followed by reaction for 30 mins.at ambient temperature (ref.65). 

The increase of the conductance of BLM when FMN is added to the functioning system (Fig. 8b) might also be connected with increase in the proton concentration in the layer adjacent to the membrane, which should lead to increase to the form Q6H2 which is inactive in electron transport but should possess the well-known property of phenol, namely, it should increase the proton conductance of BLM. Accumulation of Q6H2 in BLM is due to the fact that in solutions with a high buffer capacity the depletion in proton in the layer adjacent to the membrane is eliminated as a result of which the reaction consuming hydrogen ions... 

Draw the condensed structiue of the compounds formed by condensation reactions between (a) benzoic acid and ethanol, (b) ethanoic acid and methylamine, (c) acetic acid and phenol. Name the compoimd in each case. 

If the third substance dissolves in both liquids (and the solubility in each of the liquids is of the same order), the mutual solubility of the liquids will be increased and an upper C.S.T. will be lowered, as is the case when succinic acid or sodium oleate is added to the phenol - water system. A 0 083 molar solution of sodium oleate lowers the C.S.T. by 56 -7° this large effect has been applied industrially in the preparation of the disinfectant sold under the name of Lysol. Mixtures of tar acids (phenol cresols) do not mix completely with water at the ordinary temperature, but the addition of a small amount of soap ( = sodium oleate) lowers the miscibility temperature so that Lysol exists as a clear liquid at the ordinary temperature. 

The acylpalladium complex formed from acyl halides undergoes intramolecular alkene insertion. 2,5-Hexadienoyl chloride (894) is converted into phenol in its attempted Rosenmund reduction[759]. The reaction is explained by the oxidative addition, intramolecular alkene insertion to generate 895, and / -elimination. Chloroformate will be a useful compound for the preparation of a, /3-unsaturated esters if its oxidative addition and alkene insertion are possible. An intramolecular version is known, namely homoallylic chloroformates are converted into a-methylene-7-butyrolactones in moderate yields[760]. As another example, the homoallylic chloroformamide 896 is converted into the q-methylene- -butyrolactams 897 and 898[761]. An intermolecular version of alkene insertion into acyl chlorides is known only with bridgehead acid chlorides. Adamantanecarbonyl chloride (899) reacts with acrylonitrile to give the unsaturated ketone 900[762],... 

An old name for benzene was phene and its hydroxyl derivative came to be called phe nol This like many other entrenched common names is an acceptable lUPAC name Likewise o m and p cresol are acceptable names for the various ring substituted hydroxyl derivatives of toluene More highly substituted compounds are named as deriv atives of phenol Numbering of the ring begins at the hydroxyl substituted carbon and proceeds m the direction that gives the lower number to the next substituted carbon Sub stituents are cited m alphabetical order... 

Carboxyl and acyl groups take precedence over the phenolic hydroxyl m deter mining the base name The hydroxyl is treated as a substituent m these cases... 

Phenol IS both an important industrial chemical and the parent of a large class of compounds widely distributed as natural products Although ben zenol IS the systematic name for CgHsOH the lUPAC rules permit phe nol to be used instead Substituted derivatives are named on the basis of phenol as the parent compound... 

The lUPAC mles permit the use of common names for a number of familiar phenols and aryl ethers These common names are listed here along with their systematic names Write the stmcture of each compound... 

Tablel.10 Retained Trivial Names of Alcohols and Phenols with Structures 1.24...

Bivalent radicals of the form O—Y—O are named by adding -dioxy to the name of the bivalent radicals except when forming part of a ring system. Examples are —O—CHj—O— (methylene-dioxy), —O—CO—O— (carbonyldioxy), and —O—SOj—O— (sulfonyldioxy). Anions derived from alcohols or phenols are named by changing the final -ol to -olate. 

Some commercially important cross-linked polymers go virtually without names. These are heavily and randomly cross-linked polymers which are insoluble and infusible and therefore widely used in the manufacture of such molded items as automobile and household appliance parts. These materials are called resins and, at best, are named by specifying the monomers which go into their production. Often even this information is sketchy. Examples of this situation are provided by phenol-formaldehyde and urea-formaldehyde resins, for which typical structures are given by structures [IV] and [V], respectively ... 

Phenol—formaldehyde (PF) was the first of the synthetic adhesives developed. By combining phenol with formaldehyde, which has exceptional cross-linking abiHties with many chemicals and materials, and a small amount of sodium hydroxide, a resin was obtained. The first resins soHdified as they cooled, and it was discovered that if it was ground to a powder with a small amount of additional formaldehyde and the appHcation of more heat, the mixture would Hquify and then convert to a permanently hard material. Upon combination of the powdered resin mixture with a filler material such as wood flour, the result then being placed in a mold and pressed under heat and pressure, a hard, durable, black plastic material was found to result. For many years these resulting products were called BakeHte, the trade name of the inventor. BakeHte products are still produced today, but this use accounts for only a small portion of the PF resins used. 

Phenolphthalein. Alophen, Ex-Lax, Feen-a-Miat, Modane, and Phenolax are trade names for phenolphthaleia [77-09-8] (3,3-bis(4-hydroxyphen5l)-l-(3ff)-l isobensofuranone) (10). It is a white or faintiy yellowish white crystalline powder, odorless and stable ia air, and practically iasoluble ia water one gram is soluble ia 15 mL alcohol and 100 mL diethyl ether. Phenolphthaleia may be prepared by mixing phenol, phthaHc anhydride, and sulfuric acid, and heating at 120°C for 10—12 h. The product is extracted with boiling water, then the residue dissolved ia dilute sodium hydroxide solution, filtered, and precipitated with acid. 

Mesitylene. One of the principal derivatives of mesitylene is the stericaHy hindered phenol of the stmcture shown in Eigure 4. Its trade name is Ethanox 330 and it is produced by Albemarle Corporation (formerly Ethyl Corporation) (31). Ethanox 330 is an important noncoloring antioxidant and thermal stabiHzer for plastics, adhesives, mbber, and waxes (qv) (32,33) (see Antioxidants). The oral toxicity of Antioxidant 330 is extremely low (oral LD q in rats >15 g/kg) since its large size, C H gO, effectively eliminates absorption from the gastrointestinal tract. 

For monosubstituted alkylphenols, the position of the alkyl radical relative to the hydroxyl function is designated either with a numerical locant or ortho, meta, or para. The alkyl side chain typically retains a trivial name. Thus 4-(l,l,3,3-tetramethylbutyl)phenol, 4-/ f2 octylphenol, and para-tert-octy Tph.eno (PTOP) all refer to stmcture (1). 

For phenols with three or more alkyl substituents, trade names, abbreviations, and associative names predominate, eg, BHT and... 

A Methylamino)phenol. This derivative, also named 4-hydroxy-/V-methy1ani1ine (19), forms needles from benzene which are slightly soluble in ethanol andinsoluble in diethyl ether. Industrial synthesis involves decarboxylation of A/-(4-hydroxyphenyl)glycine [122-87-2] at elevated temperature in such solvents as chlorobenzene—cyclohexanone (184,185). It also can be prepared by the methylation of 4-aminophenol, or from methylamiae [74-89-5] by heating with 4-chlorophenol [106-48-9] and copper sulfate at 135°C in aqueous solution, or with hydroquinone [123-31 -9] 2l. 200—250°C in alcohoHc solution (186). 

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