Aliphatic halogen compounds hydrolysis

Reaction XXXVUI. (a) Action of Aqueous and Alcoholic Potassium or Sodium Cyanide on Aliphatic Halogen Compounds, and Hydrolysis of the Nitriles so formed. (B., 14, 1965 15, 2318.)—The preparation and hydrolysis of nitriles are dealt with on p. 151 and p. 239 respectively. In many cases, however, it is unnecessary to isolate the nitrile it can be directly hydrolysed to the corresponding acid on its formation. Among others, the following syntheses have been carried out in this way — i (i.) w-Valeric acid [jpentan acid] from w-butyl bromide (Am. Soc., 42, 310). 

Hydrolysis can detoxify a wide range of aliphatic and aromatic organics such as esters, ethers, carbohydrates, sulfonic acids, halogen compounds, phosphates, and nitriles. It can be conducted in simple equipment (in batches in open tanks) or in more complicated equipment (continuous flow in large towers). However, a potential disadvantage is the possibility of forming undesirable reaction products. This possibility must be evaluated in bench- and pilot-scale tests before hydrolysis is implemented. 

Introduction. The general formula for carbinols is ROH. If the radical is aliphatic, they are called alcohols, if aromatic, and the functional group (OH) is attached directly to the benzene nucleus, they are called phenols. The student already knows that one method of preparation is the hydrolysis of halogen compounds. One way to summarize the preparation of alcohols is to consider the progressive oxidation of the methane carbon atom ... 

In general, abiotic substitution reactions proceed slowly, but can be greatly accelerated by enzymes. Enzyme-mediated substitutions frequently involve cysteine residues in proteins or peptides, such as glutathione. Biotic and abiotic hydrolysis of halogenated aliphatic compounds yields alcohols by hydros l substitution at the halogenated carbon [10]. If these alcohols are themselves halogenated, further hydrolysis to acids or diols can occur. Examples of microbially-mediated hydrolysis reactions, together with responsible enzymes, are provided in Table 1. 

Aliphatic and aryl aliphatic amino ketones are made by the amination of the halogenated carbonyl compounds, - e.g., dimethylaminoacetone (74%), l-diethylamino-2-pentanone (79%), and a-methylaminopropio-phenone (57%). It is noteworthy that this system may undergo a rearrangement, viz., ArCOCH,Br+ (C,H,),NH— ArCHjCON(C,H5)a (45%). The reaction of a-halo ketones with arylamines is even more complex. Examples of the formation of a-aminoaldehydes by this method are few. However, the same results may be achieved by the amination of the halo acetals with subsequent hydrolysis. "... 

The widespread contamination of surface and groundwaters by halogenated aliphatics has prompted efforts to determine pathways for the degradation of these environmental pollutants. Hydrolysis half-lives for halogenated aliphatics range from months to years however, because residence times for these pollutants in groundwater systems are often measured in years, hydrolysis will be an environmentally significant transformation pathway for these compounds. 

Filtrate after hydrolysis with alcoholic KOH + AgNOa precipitate Halo compounds aliphatic,aromatic, and with a halogen atom in the side chain... 

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