Acetic mono-chlorination

Mikami and Takei (80) extracted tripropyltin(IV) with acetic, mono-chloroacetic, dichloroacetic, and formic acids in carbon tetrachloride. The partition constant of the extracted species, Pr3SnA (Pr = propyl A = CH3COO , CH2C1C00, and CHCl2COO ), increased with increasing chlorine substitution of acetic acid. 

The crude acetone produced in the first step of the reaction is first rid of gaseous components (unconverted propylene, propane etc.). The small amounts entrained are absorbed by scrubbing with water at 50°C and atmospheric pressure. The acetone is then distilled to separate the light ends, particularly propionaldehyde, with heavy ends separation to remove the heavy products (water, acetic add, chlorinated compounds such as mono- and dichloroacetones, mono- and dichloropropionaldehydes, etc.). Treatment with caustic soda, carried out in the same final column, facilitates the destruction of the chlorinated compounds and improves the final yield of the operation. 

Sulfonation occurs with concentrated sulfuric acid at 30° C. Nitration is accompMshed with nitric acid-acetic anhydride. Chlorination in the dark, or with SO2CI2, gives the mono-chloro derivative. 

Addition of surfactants PE/PVC, PS/Rubber non-ionic compatibilizers (Ethylene oxide-propylene oxide mix polymer). Sodium oleate, n-alcansulfonate, dodecyl benzoate. Mono chlorine acetic acid, etc. 

Selectivity is a major issue for the mono-chlorination of acetic acid to chloroacetic acid since second chlorination gives dichloroacetic acid and other chlorinated species including add chloride formation [132]. The removal of these impurities, especially of the dichloroacetic add is laborious and costly, either by crystallization or by reduction with a palladium catalyst. 

Acetic acid can be chlorinated by gaseous chlorine in the presence of red phosphorus as catalyst to yield successively mono-, di-, and tri-chloroacetic acid the reaction proceeds better in bright sunlight. If the chlorination is stopped when approximately one molecule of chlorine per molecule of acetic acid is absorbed the main product is monochloroacetic acid ... 

Lewis acid catalyst is normally required when ammonium polyhalides are used, although recourse does not have to be made to strong acids, such as aluminium trichloride. Bromination and iodination reactions are normally conducted in acetic acid in the presence of zinc chloride [32], but chlorination using the ammonium tetrachloroiodate in acetic acid does not require the additional presence of a Lewis acid [33]. Radical chlorination of toluenes by benzyltrimethylammonium tetrachloroiodate in the presence of AIBN gives mixtures of the mono-and dichloromethylbenzenes [34], Photo-catalysed side-chain chlorination is less successful [35], Radical bromination using the tribromide with AIBN or benzoyl peroxide has also been reported [36, 37],... 

Reports of electrophilic substitution are scarce, but pyridazino[2,3-. ]quinoxaline-4,4-dicarboxylates reportedly undergo bromination and chlorination at C-3 with A -halosuccinimides in acetic acid (Scheme 29). Treatment of the product with hydrazine hydrate results in hydrolysis and mono-decarboxylation <2003JHC837>. 

When 2,2-disubstituted 1,3-dioxolanes were employed, mono- or poly-chlorination of the side chain was observed on the carbon atom a to the acetal grouping. Incidentally, it should be noted thatN-bromo-succinimide, N-chlorosuccinimide, and trichlorotetrahydrotriazine-trione were found to be effective for the preparation of bromoacetates from O-ethylidene derivatives this might be useful when O-benzyli-dene derivatives are not readily available, or when a problem arises due to the fact thatO-benzoyl groups are, in general, more difficult to remove than O-acetyl groups. 

Mono- and Diglycerides occur as a substance that varies in consistency from yellow liquids through white- to pale yellow-colored plastics to hard, ivory-colored solids. They consist of mixtures of glycerol mono- and diesters, with minor amounts of triesters, and of edible fats or oils or edible fat-forming fatty acids. They are insoluble in water, but are soluble in alcohol, in ethyl acetate, and in chloroform and other chlorinated hydrocarbons. 

Metabolism of 1,1-dichloroethane by hepatic microsomes resulted in the production of acetic acid as the major metabolite and 2,2-dichloroethanol, mono-, and dichloroacetic acid as minor metabolites (Table 2-4) (McCall et al. 1983). On the basis of these results, pathways for the metabolism of 1,1-dichloroethane were proposed (Figure 2-3). The initial steps in the metabolism of 1,1-dichloroethane were proposed to involve cytochrome P-450-dependent hydroxylations at either carbon. Hydroxylation at C-1 would result in the production of an unstable alpha-haloalcohol, which can lose HCI to yield acetyl chloride. An alternative, but less favorable reaction, would be a chlorine shift to yield chloroacetyl chloride. These acyl chlorides can react with water to generate free acids or react with cellular constituents. Hydroxylation at C-2 would produce 2,2-dichloroethanol, which would undergo subsequent oxidation to dichloroacetaldehyde and dichloroacetic acid (McCall et al.1983). 

PROP A chlorinated polycyclic ketone. A cr "Stalline material. Mp decomp 350°. Sltly water-sol sol in ale, ketones, and acetic acid. Readily hydrates on exposure to room temperature and humidity normally used as a mono- to trihydrate (NCIBR ). 

Chlorination of phenazine in refluxing carbon tetrachloride in the presence of sodium acetate yields a mixture of 1-chloro- (32%) and 1,4-dichlorophenazine (25%) chlorination of phenazine in hydrochloric acid gives a mixture of mono- and polychlorinated compounds. Bromination of phenazine with bromine in acetic acid affords 1,4,6,9-tetrabromophenazine (see Houben-Weyl, Vol. 5/4, p 330). 

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