Phenol occurrence

Ahlborg UG, TM Thunberg (1980) Chlorinated phenols occurrence, toxicity, metabolism, and environmental impact. CRC CritRev Toxicol 1 1-35. 

Ahlborg, U. G. Thurnberg, T. M. (1980). Chlorinated phenols occurrence, toxicity, metabolism, and environmental impact. Critical Reviews in Toxicology, 7, 1-35. Allard, A-S., Remberger, M. Neilson, A. H. (1987). Bacterial O-methylation of halogen substituted phenols. Applied and Environmental Microbiology, 53, 839—45. 

Ahlborg, U. G., and T. M. Thunberg. 1980. Chlorinated Phenols Occurrence, Toxicity, Metabohsm and Environmental Impact, CRC Critical Review of Toxicology, vol. 7, pp. 1-35. 

Under the same conditions the even more reactive compounds 1,6-dimethylnaphthalene, phenol, and wt-cresol were nitrated very rapidly by an autocatalytic process [nitrous acid being generated in the way already discussed ( 4.3.3)]. However, by adding urea to the solutions the autocatalytic reaction could be suppressed, and 1,6-dimethyl-naphthalene and phenol were found to be nitrated about 700 times faster than benzene. Again, the barrier of the encounter rate of reaction with nitronium ions was broken, and the occurrence of nitration by the special mechanism, via nitrosation, demonstrated. 

The process is carried at moderate (slightly above atmospheric) pressures, but at very high temperatures that reach a maximum of 1900°C. Even though the reaction time is short (0.6—0.8 s) the high temperature prevents the occurrence of any condensable hydrocarbons, phenols, and/or tar in the product gas. The absence of Hquid simplifies the subsequent gas clean-up steps. 

Scheme 4b depicts condensation between a hydroxymethyl group and a phenolic ring where the hydroxybenzyl attacks at a ring position that is already hydroxymethylated. In this case, a methylene linkage is produced between the rings with concurrent loss of one mole each of formaldehyde and water. Both Jones and Grenier-Loustalot et al. demonstrated the occurrence of this reaction pathway beyond doubt under basic conditions. 

The occurrence of arenediazo alkyl and aryl ethers as intermediates has been discussed since 1870, when Kekule and Hidegh postulated that in the azo coupling reaction of benzenediazonium salts with phenol, 4-phenylazophenol is formed via the diazo phenyl ether. The analogous problem for diazo methyl ethers was first discussed by von Euler (1903). 

Tenerife and La Palma, revealed the existence of luteolin and an array of simple phenolic derivatives as well as three known phytosterols, B-amyrin, sitosterol, and stigmasterol. The phenols identified comprised a set of phenylpropanoids myristicin [566] (see Fig. 6.16 for structures 566-573), methyleugenol [567], todadiol [568], todatriol [569], crocatone [570], elemicin [571], apiole [572], and the coumarin scopoletin [573]. The occurrence of these compounds is recorded in Table 6.5. The differences between the two profiles were taken by Gonzalez and his co-workers... 

Fetterer, R.H. and Hill, D.E. (1993) The occurrence of phenol oxidase activity in female Trichuris suis. Journal of Parasitology 79, 155—159. 

Phenolic Compounds Chemistry and Occurrence in Fruits and Vegetables... 

Clifford MN. 2000b. Miscellaneous phenols in foods and beverages—nature, occurrence and dietary burden. J Sci Food Agric 80(7) 1126-1137. 

Navarro A, Lacorte S, Barcelo D (2010) Occurrence and transport of pesticides and alkyl-phenols in water samples along the Ebro river basin. J Hydrol 383 18-29... 

D2. Dent, C. E., A study of the behaviour of some sixty amino acids and other ninhydrin reacting substances on phenol-collidine filter paper chromatograms with notes as to the occurrence of some of them in biological fluids. Biochem. J. 43, 169-180 (1948). 

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