P-chlorophenol

Prepared by condensing p-chlorophenol with phlhalic anhydride in sulphuric acid solution in the presence of boric acid. The chlorine atom is replaced by hydroxyl during the condensation. It can also be prepared by oxidation of anthraquinone or 1-hydroxyanthraquinone by means of sulphuric acid in the presence of mercury(ll) sulphate and boric acid. 

Nltroso-4-chlorophenol copper chelate (4) A solution of p-chlorophenol 3 (12 85 g,... 

A mixture of 200 parts of p-chlorophenol, 1,000 parts of acetone and 360 parts of sodium hydroxide pellets is heated under reflux and 240 parts of chloroform are gradually added at such a rate that the mixture continues to reflux without further application of heat. 

Harano and colleagues [48] found that the reactivity of the Diels-Alder reaction of cyclopentadienones with unactivated olefins is enhanced in phenolic solvents. Scheme 6.28 gives some examples of the cycloadditions of 2,5-bis-(methoxycar-bonyl)-3,4-diphenylcyclopentadienone 45 with styrene and cyclohexene in p-chlorophenol (PCP). Notice the result of the cycloaddition of cyclohexene which is known to be a very unreactive dienophile in PCP at 80 °C the reaction works, while no Diels-Alder adduct was obtained in benzene. PCP also favors the decarbonylation of the adduct, generating a new conjugated dienic system, and therefore a subsequent Diels-Alder reaction is possible. Thus, the thermolysis at 170 °C for 10 h of Diels-Alder adduct 47, which comes from the cycloaddition of 45 with 1,5-octadiene 46 (Scheme 6.29), gives the multiple Diels-Alder adduct 49 via decarbonylated adduct 48. In PCP, the reaction occurs at a temperature about 50 °C lower than when performed without solvent, and product 49 is obtained by a one-pot procedure in good yield. 

Clofibrate causes a necrotizing myopathy, particularly in patients with renal failure, nephrotic syndrome or hypothyroidism. The myopathy is painful and myokymia of unknown origin is sometimes present. The mechanism of damage is not known, but p-chlorophenol is a major metabolite of clofibrate and p-chlorophe-nol is a particularly potent uncoupler of cellular oxidative phosphorylation and disrupts the fluidity of lipid membranes. Muscle damage is repaired rapidly on the cessation of treatment. 

The results for the hydrolysis of chlorobenzene, o-chlorotoluene and p-chloroanisole in presence of cuprous oxide at different temperatures (Fig. 14) show a good selectivity for the reaction of the chlorobenzene. But, the p-chloroanisole is also transformed by a secondary demethylation reaction into the corresponding p-chlorophenolate. 

Dechlorination of Aromatics Investigated in Micro Reactors Cas/liquid reaction 15 [CL 15] Dechlorination of p-chlorophenol to phenol... 

P 14] A solution containing p-chlorophenol was fed from a 250 ml flask to the micro reactor by a syringe pump [20]. Flow rates from 10 to 65 ml min were applied. The reaction temperature was set to either 20 or 40 °C. 

GL 15] ]R 7] ]P 14] During a 24 h period, only minimal deactivation could be detected [20], Only about 10-15% of the p-chlorophenol was converted. 

JOVANOVIC, G., Sacrittichai, P., Toppinen, S., Microreactors systems for dechlorination of p-chlorophenol on palladium based metal support catalyst theory and experiment, in Proceedings of the 6th International Conference on Microreaction Technology, IMRET 6, 11-14 March 2002, pp. 314-325, AIChE Pub. No. 164, New Orleans (2002). 

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