Phenol with sulfuric acid

Hydroquinone (HQ) is prepared by the oxidation of phenol. Resorcinol can be prepared by the oxidation of m-diisopropylbenzene. Biphenol is prepared by the oxidative dimerization of 2,6-di-ten-butyl phenol and subsequent debutylation. 4,4 -Dihydroxydiphenyl sulfone can be prepared by reacting phenol with sulfuric acid. Phenolphthalein can be obtained... 

It is of great commercial interest for the preparation of PES. It can be prepared by reacting phenol with sulfuric acid, without using a solvent. Such processes give a crude product with 60-70% bis-(4-hydroxyphenyl)-sulfone. 

The O acylation of phenols with carboxylic acid anhydrides can be conveniently catalyzed m either of two ways One method involves converting the acid anhydride to a more powerful acylatmg agent by protonation of one of its carbonyl oxygens Addi tion of a few drops of sulfuric acid is usually sufficient... 

These peroxides also form 1 1 adducts with styrene and form hydroben2oin diarenesulfonates with stilbenes. Di(ben2enesulfonyl) peroxide decomposes in water to phenol and sulfuric acid (33). 

A A Dimethylamino)phenol. 4-Hydroxy-Ai,A/-dimethylaniline (20) forms large rhombic crystals from diethyl ether—hexane or diethyl ether—ligroin. It forms a salt with sulfuric acid, mp 208—210°C (187). 

Phenol reacts with some acryUc acid derivatives to produce coumaria. With 3-ethoxyacryHc acid chloride, phenol gives phenyl ethoxyacrylate that cyclizes iato coumaria on treatment with sulfuric acid (41). Coumaria is also formed by reactioa of pheaol with methyl acrylate ia acidic medium and ia the presence of air (42). 

More recent prepns are by the reaction of tetra-fluorohydrazine (F2NNF2) with thio phenol, yield up to 74% (Ref 7) by treatment of tri-phenylmethyldifluoramine with sulfuric acid, yield almost quant, purity by mass spec 99%... 

Tetralin and 1-methylnaphthalene were reagent grade and were used after washing with sulfuric acid, alkali, and water and the subsequent distillation at 70°C under reduced pressure. Various additives and model compounds were reagent grade, and some of them were used after recrystallization. Phenyl naphthyl ether and phenyl 9-phenanthryl ether were synthesized by refluxing a mixture of aryl bromide, phenol, CU2O and X-collidine (12). 

These compounds contain the fragment R as an alkyl or aryl moiety. In other words, they result from the esterification of an alcohol or a phenol with nitrous acid, nitric acid, phosphoric acid, sulfuric acid, or sulfamic acid, respectively. Many of the esters to be examined in this chapter must be activated prior to eliciting their effects, e.g., the organic nitrites and nitrates, which act as donors of nitric oxide or an analogous molecule, and phosphates, which are activated by hydrolysis or even by phosphorylation (antiviral agents). Sulfates are very seldom active or used as prodrugs, but they have significance as metabolites and as industrial xenobiotics. 

The early sources of phenol were the destructive distillation of coal and the manufacture of methyl alcohol from wood. In both cases, phenol was a by-product. Recovered volumes were limited by whatever was made accidentally in the process. Initial commercial routes to on-purpose phenol involved the reaction of benzene with sulfuric acid (1920), chlorine (1928), or hydrochloric acid (1939) all these were followed by a subsequent hydrolysis step (reaction with water to get the -OH group) to get phenol. These processes required high temperatures and pressures to make the reactions go. They re multistep processes requiring special metallurgy to handle the corrosive mixtures involved. None of these processes is in commercial use today. 

The amine is then used to introduce a nitrile by diazotization followed by treatment of the diazonium salt with cuprous cyanide (180) the methyl ether is then cleaved by means of aluminum chloride. Treatment of the phenolic ketone 181 with benzoyl chloride and sodium benzoate serves to build up the chromone ring (182). The nitrile is next hydrolyzed to the acid with sulfuric acid. Esterification of the carboxyl as—its acid chloride—with N-(2-hydroxyethyl)piperi-... 

These carbonaceous catalysts can be obtained by the sulfonation of incompletely carbonized organic compounds [42]. Note that starch and cellulose can be used as carbon precursor [43, 44]. After the incomplete pyrolysis of the carbon precursor, the SO3H groups have been introduced by sulfonation with sulfuric acid (Scheme 3). After this treatment, the presence of phenolic hydroxyl, carboxylic acid, and sulfonic groups at the surface of these amorphous carbonaceous materials has been demonstrated. 

MeCOCH2CH(OMe)2 and EtOCH=CHCH(OEt)2, with sulfuric acid catalysis, gave 42, (R = Me and R = H, respectively). 1-Hydroxycarbazole behaved comparably, no interaction with the phenolic hydroxyl occurring. 

Picric acid (7.1) can be prepared by dissolving phenol in sulfuric acid and then nitrating the product with nitric acid as shown in Reaction 7.1. 

Aryl acetoacetates, which may be obtained by the reaction of phenols with diketene, are cyclized on treatment with sulfuric acid (54JCS854). The yields of coumarins are similar to those obtained by a Pechmann reaction on the phenol. 

The aqueous phase from the previous step, after extracting methyl ethers of phenolics, was acidified to a pH of 1-2 with sulfuric acid, and the free acids were extracted continuously with ether by the procedure previously noted. The ether extract was brought to volume and divided into aliquots for analysis. The methyl esters of the acids were formed by distilling an excess of diazomethane into an ether aliquot containing the free acids plus 10% methanol. When esterification was completed (approximately 20 min.), the ether solution was purged with nitrogen to remove excess diazomethane and was reduced in volume. This solution was analyzed immediately by GLC. 

Samples collected for total phenolics analysis by distillation are preserved with sulfuric acid to stop bacterial degradation and oxidation. 

Although it has been stated that only phenols are conjugated with sulfuric acid,1 three urinary steroid sulfate esters (androsterone sulfate, dehydro-epi-androsterone sulfate, and A 6-aZZo-pregnene-3(/3)-ol-20-one sulfate) have been isolated in which the sulfuric acid is esterified by an alcoholic hydroxyl group.111 It is true that no alcohol administered to... 

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