O-Chlorophenol

The main characteristics and physical properties of the chlorophenols are brought together in Table 1. With the exception of o-chlorophenol, they are all sohds at room temperature. The refractive indexes of the monochlorophenols, C H CIO, are as follows ortho, 1.5524 meta, 1.5565 para, 1.5579. The piC values of chlorophenols depend on the number and the position of the substituents. 

Dichlorophenols. Among all the dichlorophenols, C H Cl O, it is 2,4-dichlorophenol that is produced in greatest quantity. 2,4-Dichlorophenol is used in manufacturing 2,4-dichlorophenoxyacetic acid [94-75-7] (2,4-D) and 2-(2,4-dichlorophenoxy)propionic acid [720-36-5] (2,4-DP). Industrially, 2,4-dichlorophenol can be obtained by chlorinating phenol, -chlorophenol, o-chlorophenol, or a mixture of these compounds in cast-iron reactors. The chlorinating agent may be chlorine or sulfuryl chloride in combination with a Lewis acid. For example ... 

Chlorination with SO2CI2, which is favorable to the para isomer at the monochlotination stage, gives an excellent yield of 2,4-dichlorophenol. Startiag with (9-chlorophenol, it is possible to attain a selectivity for 2,4-dichlorophenol of 98%, if chlotination is carried out ia Hquid SO2 at low temperature (20). 2,6-Dichlorophenol is also used as an iatermediate. It is obtained by chlotinatiag o-chlorophenol ia the presence of a catalytic quantity of an amine, with or without a solvent medium (21,22), giving a yield of 90%. 

For aromatic alcohols and compounds with an----OH on a side chain, the alcohol contribution (primary, etc.) must be included. For example, o-chlorophenol ... 

Column performance is maintained during solvent exchange. Hhr and SuperH columns are compatible with the following solvents acetone, benzene, carbon tetrachloride, chloroform, 1-chloronaphthalene, o-chlorophenol. 

Acetone Carbon tetrachloride, chloroform/o-chlorophenol, chloroform// -cresol, chloroform/hexafluoroisopropanol, chloroform/methanol (up to 60%), o-dichlorobenzene, dimethylformamide, dimethyl sulfoxide, dioxane, ethylacetate, FC-113, haxane, methylethylketone, N-methylpyrrolidone, pyridine, quinoline, cyclohexane, dodecane... 

In a 2 liter round-bottomed flask equipped with stirrer and dropping funnel is placed 1,585 grams (880 cc 13.6 mols) of chlorosulfonic acid. To this is added dropwise with stirring during 5 hours 218 grams (1.7 mols) of o-chlorophenol. The mixture is allowed to stand 1 hour at room temperature and then is heated 1 hour on a steam bath. The mixture is then poured on ice. 

Poly(alkylene terephthalate)s are soluble only in solvents such as 1,1,2,2-tetrachloroethane-phenol or o-cresol-CHCl3 mixtures, o-chlorophenol,... 

DBpD was prepared by slowly heating a mixture of o-chlorophenol (480 mmoles), potassium carbonate (240 mmoles), and purified copper powder (50 mmoles) in a 500-ml Erlenmeyer flask to 160°-180°C and maintaining this temperature for 6 hours. DBpD, which sublimed to the walls of the flask as it was formed, was recovered by scraping and was recrystallized from absolute ethanol (14% yield white needles, mp 119°-120°C reported 120°-122°C (7) elemental analyses—calcd. C = 78.26, H = 4.34, found C = 77.98, H = 4.48). 

The precursor of poly(penzoxazole) (28), poly(o-hydroxy amide) (27) is amorphous and readily soluble in DMF, NMP, DMSO, pyridine, THF, and acetone.25 Transparent, flexible, and tough film of 27 can be obtained by casting. However, fluorine-containing poly(benzoxazole) (28) from 25 dissolves only in concentrated sulfuric acid and o-chlorophenol. 

The aromatic poly(benzothiazole) from 15 and 29 is almost amorphous and easily soluble in strong acids such as concentrated sulfuric acid and methane-sulfonic acid.26 It also dissolves in organic solvents such as HMPA and o-chlorophenol. The increased solubility and amorphous nature of this polymer is also ascribed to reduced intermolecular forces and to looser packing owing to the presence of highly distorted diphenylhexafluoroisopropylidene units in the polymer backbone. 

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