Phenol, p-

If phenol is heated with more concentrated nitric add (in the presence of sulphuric acid), nitration occurs ultimately at the para and at both the ortho positions, giving picric acid or 2,4,6-trinitrophenol. To prepare picric acid, however, it is more convenient first to heat the phenol with sulphuric acid, whereby a mixture of 0- and p-phenol sulphonic acids is readily obtained. If this mixture is now heated with concentrated nitric acid, nitration occurs at the... 

The complex batch reaction between formaldehyde. A, and sodium p-phenol sulphonate, B, proceeds in accordance with the following complex reaction scheme. All the reactions follow second-order kinetics. Components C, D and F are intermediates, and E is the final product. 

Sanchez, A. J. Konopelski, J. P. Phenol benzylic epoxide to quinone methide electron reorganization synthesis of ( )-taxodone. J. Org. Chem. 1994, 59, 5445-5452. 

The dienone intermediate (53a), as well as enolising to the phenol (52a), is itself capable of undergoing a Cope rearrangement to yield a second dienone (cf. 56a), whose enol is the p-substituted phenol (c/ 57a). Enolisation normally predominates, but where (51) has o-substituents, i.e. (54a), o-enolisation cannot take place, and only the p-phenol (57a) is then obtained. That this product is indeed formed not by direct migration of the allyl group, but by two successive shifts, is suggested by the double inversion of the position of the, 4C label in the allyl group that is found to occur ... 

FIGURE 2.1 Reaction scheme for OPH hydrolysis of methyl parathion and paraoxon (a) followed by the electrochemical oxidation of p-phenol (b). R and R are ethoxy and methoxy and X is O and S in paraoxon and methyl parathion, respectively. 

Fig. 2.1.7. Possible structures for the nonylphenol isomers 2(p-phenol)-methyloctane. indicates asymmetric carbon atom.

Parr, A.J. and Bolwell, G.P., Phenols in the plant and in man. The potential for possible nutritional enhancement of the diet by modifying phenolic content or composition, J. Sci. Pood Agric., 80, 985, 2000. 

Pauli, G.F. and Junior, P., Phenolic glycosides from Adonis aleppica. Phytochemistry, 38, 1245, 1995. 

Resorcinol/phenol-formaldehyde condensation products prepared by Durairaj et al. (3) using zinc acetate as the reaction catalyst contained 2% / -//-phenolic, 16% -p -phenolic, 64% o-o -phenolic-4-4 -resorcinolic, 16% 2-4 -resorcinolic, and 2% 2-2 -resorcinolic methylene bridges. 

Singleton, V. L., Esau, P., Phenolic Substances in Grapes and Wine, and... 

Benzydamine (373), an analgesic and antiinflammatory drug, generates p-phenolic metabolite 374 despite several competing reactions.230... 

AA, acetic anhydride AcOH, acetic acid P. phenol, PA, phenyl acetate. 

Photochemical processes of CD complexes,1 Differences in photochemical reactions conducted in solution and in CD complexes have been reviewed. For example, photo-Fries rearrangement of phenyl esters in solvents results in a mixture of o- and p-phenolic ketones via a radical reaction. Rearrangement of the same encapsulated ester results in exclusive rearrangement to the ortho-position (equa-... 

To the extension mixture from Step 2 add 25 p phenol (redistilled, water-saturated). 

Etherified Phenolic Structures Containing fi-Aryl Ether Bonds In ether-ified p-phenolic structures the/3-aryl ether linkage is cleaved by hydroxide... 

Liquid Phase Condensed Oils (high P) (phenols, aromatics) Primary Liquids (low P, short x) (oxygenates) Condensible Tars (BTX, phenols, aromatics) ... 

The phenolic functions are deprotected under rather drastic conditions, by analogy with methods defined previously for the cleavage of aryl methyl ethers.14 Treatment of dianisylphenanthroline 4 with pyridinium hydrochloride at 210°C affords 2,9-di(p-phenol)-l,10-phenanthroline 5 quantitatively (Scheme 9.4). 

Reaction of one equivalent of diiodo acyclic link molecule 7 with one equivalent of 2,9-di(p-phenol)-l,10-phenanthroline 5 under high-dilution conditions in the presence of a large excess of caesium carbonate affords the chelating macrocyle 8 in 45% yield (Scheme 9.6). 

XS = sulfonation, M = methylolation, MO = miscellaneous oxidation, G = grafting, P = phenolation, CM = carboxymethylation, MAC = maleic anhydride copolymerization, MCR = miscellaneous carboxyla-tion reactions, E = epichlorohydrin (also in conjunction with pheno-lated lignin), A = alkoxylation (i.e., ethylene, propylene, and butylene oxides), M+EP = modification with compounds containing unsaturated end groups ( divalent hydrocarbons ) followed by epoxidation with peroxide, MA = methacrylic acid. 

DegussaAG Butyl phenol, p- Phenol, isobutylene Continuous alkylation of phenol with heterogeneous catalyst NA NA... 

A method for preparing thermosets by modifying o,p-phenol-formaldehyde resins using paraformaldehyde and aniline to provide A-phenyl benzoxazine having a melt viscosity between 2 and 4 poise at 125°C is described. 

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