Dichlorophene

Another important bisphenol is dichlorophene (dichlorophane, methylene-bis(4-chlorophenol)) [97-23-4]. Whereas it is not as active against bacteria as hexachlorophane, it has found miscehaneous apphcations, eg, as a rot preservative for textiles (89) as a treatment for athlete s foot and for tapeworm in humans and domestic animals as a slimicide in paper manufacture and as an antibacterial agent in water-cooling systems (90). 

C4H5CIO 106-48-9) see Amoxapine Chlorphenesin Clofiijrate Dichlorophen Dodeclonium bromide Fenticlor... 

Dichlorodibenzo-p-dioxin was prepared from isotopic potassium 2,4-dichlorophenate uniformly labeled with Ullman conditions gave a 20.5% yield. Small amounts of dichlorophenoxy chlorophenol were removed from the product by extraction with sodium hydroxide before purification by fractional sublimation and recrystallization from anisole. Chlorination of 2,7-dichlorodibenzo-p-dioxin in chloroform solution containing trace amounts of FeCls and 12 yielded a mixture of tri-, tetra-, and pentachloro substitution products. Purification by digestion in boiling chloroform, fractional sublimation, and recrystallization from anisole was effective in refining this product to 92% 2,3,7,8-tetrachloro isomer, which also contained 7% of the tri- and 1% of the penta-substituted dibenzo-p-dioxin. Mass spectroscopy was used exclusively to monitor the quality of the products during the synthesis. 

Figure 2. Preparation of 2,3,7,8-tetrachlor odi-henzo-p-dioxin from potassium 2,4-dichlorophenate...

Muelder and Shadoff (3) prepared C-2,3,7,8-Cl4-DBpD (0.9 mCi/ mmole) by chlorination of C-2,7-dichlorodibenzo-p-dioxin made from potassium C-2,4-dichlorophenate. The preparation of tritium-labeled 2,3,7,8-Cl4-DBpD is justified because the radiolabeled intermediates are less expensive and more accessible and because a higher specific activity is potentially attainable. Here, we consider the optimal conditions for the reaction sequence designed to obtain products of high chemical and radiochemical purity shown at the top of p. 8. 

For lower chlorinated phenates the reactions become even more complicated. The phenols vaporize without decomposition, and the sodium salts react in the melt (Figure 5), as shown for sodium 2,4-dichlorophenate. The relative amount of dioxins produced is lower in favor of more highly condensed material. 

Preparations of 2,7-dichlorodibenzo-p-dioxin based on the condensation of sodium 2,4-dichlorophenate have typical yields of less than 20% (4, 5, 6, 7). The formation of polymeric side-reaction products under these conditions suggests preferential nucleophilic attack at the para position (Reaction 1). 

Diazo aminobenzene Di-t-butyl-p-cresol Dibutyl tin maleate Dibutyl tin oxide Dichlorophene 2,4-Dichiorophenoxy ethyl benzoate... 

Dichlorophen is a safe, narrow-spectrum drug that, in addition to its bactericidal and fungicidal properties, has been used as a teniacide in veterinary medicine for many years. It is administered to sheep as a tablet or suspension at a dosage of 0.5g/2.5 kg bw. The insolubility of dichlorophen in water limits its absorption from the gastrointestinal tract and probably accounts for its low toxicity. Worms are killed in the gut where they disintegrate prior to expulsion in the feces. 

Chem. Abstr. Serv. Reg. No.. 120-83-2 Chem. Abstr. Name. 2,4-Dichlorophenol lUPAC Systematic Name. 2,4-Dichlorophenol Synonym. 2,4-Dichlorophenic acid... 

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