Magnesium with phenols

Magnesium and aluminum metal will react directly with phenol at its boiling point.1911 However, in both cases the inert oxide film must be mechanically removed or chemically dissolved. 

Magnesium phenoxide is obtained in a commercial process by heating MgO with phenol,10 while V2Os has been reported to yield OV(OPh)3 on heating with phenol.73... 

Strontium nitrate Magnesium Polyvinylchloride Phenol formaldehyde (with yellow dye)... 

Melamine resins are used from this group of thermosets for the manufacture of food contact materials. The melamine can be used in mixtures with urea and in some applications with phenol (< 1 %). The polymerization process is catalyzed in the presence of organic acids (e.g. acetic acid, lactic acid, tartaric acid, citric acid), hydrochloric acid, sulfuric acid, phosphoric acid, sodium and potassium hydroxide, ammonia, calcium or magnesium hydroxide as well as salts of these substances (total < 1 %) which cause the elimination of water and lead to a cured resin system. Stearic acid can be used as a lubricant as can zinc, calcium and magnesium salts, esters of montanic acid with ethandiol and 1,3-butandiol, as well as silicone oil (total < 1 %). 

Both one-part and two-part neoprene sealants are made most commonly using general purpose neoprenes of the GN and W types. Two-part compositions contain 25-30% neoprene plasticized with materials such as dioctyl sebacate or resinous plasticizers, stabilized with phenolic antioxidants, filled with reinforcing pigments such as carbon black and hard clays, and modified with cure-rate regulators and acid acceptors such as zinc oxide and magnesium oxide. Cure accelerators such as polyamines (i.e., tetraethylene pentamine) are used at 5-10 phr based on neoprene. Heat-reactive phenolic resins are also effective. One such composition is shown in Table 12. 

Formic acid reduces ammoniacal silver nitrate (see p. 210), and if reduced with magnesium in hydrochloric acid, it yields formaldehyde, which can easily be detected with chromotropic acid. In the presence of cone, sulfuric acid formic acid reacts with phenols with the formation of corresponding triphenylmethane dyes (see p. 196). 

Chlorobenzene. Prepare a solution of phenyldiazonium chloride from 31 g. (30 -5 ml.) of aniUne, 85 ml. of concentrated hydrochloric acid, 85 ml, of water, and a solution of 24 g. of sodium nitrite in 50 ml. of water (for experimental details, see Section IV,60). Prepare cuprous chloride from 105 g. of crystallised copper sulphate (Section 11,50,1), and dissolve it in 170 ml. of concentrated hydrochloric acid. Add the cold phenyl diazonium chloride solution with shaking or stirring to the cold cuprous chloride solution allow the mixture to warm up to room temperature. Follow the experimental details given above for p-chlorotoluene. Wash the chlorobenzene separated from the steam distillate with 40 ml. of 10 per cent, sodium hydroxide solution (to remove phenol), then with water, dry with anhydrous calcium chloride or magnesium sulphate, and distil. Collect the chlorobenzene (a colourless liquid) at 131-133° (mainly 133°), The yield is 29 g. 

Concentrate the mother liquors from this recrystallisation and combine with the oily filtrate dissolve in 250 ml. of 10 per cent, sodium hydroxide solution, and extract with two 50 ml. portions of ether to remove non-phenolic products. Acidify the alkaline solution with hydrochloric acid, separate the oily layer, dry it over anhydrous magnesium sulphate, and distil under diminished pressure, preferably from a Claisen flask with fractionating side arm (Figs. II, 24, 2-5). Collect the o-propiophenol (65 g.) at 110-115°/6 mm. and a further quantity (20 g.) of crude p-propiophenol at 140-150°/ 1 mm. 

Ojj 1.5323, prepared from phenol, KOH in ethanol and propargyl bromide) was added and the mixture was heated at 60°C for 15 min. It was then poured into 200 ml of ice-water and the reaction products were extracted with diethyl ether. The ethereal extracts were washed with saturated NH Cl solution, dried over magnesium sulfate and then concentrated in a water-pump vacuum. There remained 9.5 g of 3 1 mixture... 

Detergents are metal salts of organic acids used primarily in crankcase lubricants. Alkylbenzenesulfonic acids, alkylphenols, sulfur- and methjiene-coupled alkyl phenols, carboxyUc acids, and alkylphosphonic acids are commonly used as their calcium, sodium, and magnesium salts. Calcium sulfonates, overbased with excess calcium hydroxide or calcium carbonate to neutralize acidic combustion and oxidation products, constitute 65% of the total detergent market. These are followed by calcium phenates at 31% (22). 

Triaryl phosphates are produced by reaction of phosphoms oxychloride with phenoHc compounds at 100—200°C with magnesium or aluminum chloride catalyst. Past use of cresols and xylenols from coal tar or petroleum is replaced for lower toxicity and cost by synthetic phenoHcs, primarily isopropyl phenol, /-butyl phenol, and phenol itself A range of viscosities is achieved by selection and proportioning of the phenols and their isomers used for the starting material. 

Organic compounds normally cause Htde or no corrosion of magnesium. Tanks or other containers of magnesium alloys are used for phenol [108-95-2] methyl bromide [74-96 ] and phenylethyl alcohol [60-12-8]. Most alcohols cause no more than mild attack, but anhydrous methanol attacks magnesium vigorously with the formation of magnesium methoxide [109-88-6]. This attack is inhibited by the addition of 1% ammonium sulfide [12135-76-1] or the presence ofwater. 

The second processing step, in which benzoic acid is oxidized and hydrolyzed to phenol, is carried out in two reactors in series. In the first reactor, the benzoic acid is oxidized to phenyl benzoate in the presence of air and a catalyst mixture of copper and magnesium salts. The reactor is operated at 234°C and 147 kPa gauge (1.5 kg/cm g uge). The phenyl benzoate is then hydrolyzed with steam in the second reactor to yield phenol and carbon dioxide. This occurs at 200°C and atmospheric pressure. The overall yield of phenol from benzoic acid is around 88 mol %. Figure 2 shows a simplified diagram for the toluene—benzoic acid process. 

The reaction of alcohols and acid chlorides in the presence of magnesium has been described (68). With primary and secondary alcohols the reaction is very smooth, and affords high and sometimes quantitative yields. Difficulty esteritiable hydroxy compounds such as tertiary alcohols and phenols can be esteritied by this method. The reaction carried out in ether or benzene is usually very vigorous with evolution of hydrogen. 

The most common impurities are the corresponding acid and hydroxy compound (i.e. alcohol or phenol), and water. A liquid ester from a carboxylic acid is washed with 2N sodium carbonate or sodium hydroxide to remove acid material, then shaken with calcium chloride to remove ethyl or methyl alcohols (if it is a methyl or ethyl ester). It is dried with potassium carbonate or magnesium sulfate, and distilled. Fractional distillation then removes residual traces of hydroxy compounds. This method does not apply to esters of inorganic acids (e.g. dimethyl sulfate) which are more readily hydrolysed in aqueous solution when heat is generated in the neutralisation of the excess acid. In such cases, several fractional distillations, preferably under vacuum, are usually sufficient. 

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