Alcohols Ziegler reaction

Although the Ziegler reaction provides a more direct method for produciag primary alcohols, aluminum alkyl chemistry requires special handling and is fairly cosdy. The by-product aluminum salts usuaUy require some treatment for disposal (115). 

The termination of Ziegler-Natta synthesis is obtained by neutralisation of the catalytic site using, for instance, alcohol. The reaction can also simply be stopped (with no clear termination) by embedding of the catalyst into the polymer. Industrially, the control of final molecular mass is often accomplished by a hydrogen transfer reaction (see Figure 28). 

The Ziegler process, based on reactions discovered in the 1950s, produces predorninandy linear, primary alcohols having an even number of carbon atoms. The process was commercialized by Continental Oil Company in the United States in 1962, by Condea Petrochemie in West Germany (a joint venture of Continental Oil Company and Deutsche Erdid, A.G.) in 1964, by Ethyl Corporation in the United States in 1965, and by the USSR in 1983. 

Eatty alcohols, prepared from fatty acids or via petrochemical processes, aldol or hydroformylation reactions, or the Ziegler process, react with ammonia or a primary or secondary amine in the presence of a catalyst to form amines (10—12). 

Alternatively, the intermediate acetaldehyde (qv) for this process was obtained from ethylene by the Wacker process (9). A small amount of -butyl alcohol is produced in the United States by the Ziegler-Natta chain growth reaction from ethylene [74-85-1] (10). 

Linear alcohols used for the production of ethoxylates are produced by the oligomerization of ethylene using Ziegler catalysts or by the Oxo reaction using alpha olefins. 

Oligomerization of ethylene using a Ziegler catalyst produces unbranched alpha olefins in the C12-C16 range by an insertion mechanism. A similar reaction using triethylaluminum produces linear alcohols for the production of biodegradable detergents. 

Linear alcohols (C12-C26) are important chemicals for producing various compounds such as plasticizers, detergents, and solvents. The production of linear alcohols by the hydroformylation (Oxo reaction) of alpha olefins followed by hydrogenation is discussed in Chapter 5. They are also produced by the oligomerization of ethylene using aluminum alkyls (Ziegler catalysts). 

Deng, L., Ziegler, T., 1997, Theoretical Study of the Oxidation of Alcohols to Aldehyde by d° Transition-Metal-Oxo Complexes Combined Approach Based on Density Functional Theory and die Intrinsic Reaction Coordinate Method , Organometallics, 16, 716. 

C. Usually the polymerisation is carried out in the presence of Ziegler-Natta catalysts based on titanium tetrachloride and aluminium alkyl. The catalyst may be either prepared or formed in the reactor. Usually, the polymerisation is carried out in presence of a hydrocarbon solvent. The polymer is insoluble in the solvent. The reaction is terminated by addition of an alcohol and catalyst extracted with alcoholic hydrochloric acid. Catalyst removal is important for electrical insolution used. The Polymer chain obtained by this process is essentially linear. 

When ethylene reacts with triethyl- or tripropylaluminum, multiple carbometa-lation takes place, resulting in the formation of oligomers.509 Oxidation of the products followed by hydrolysis yields alcohols, whereas displacement reaction produces terminal alkenes that are of commercial importance.510 Transition-metal compounds promote the addition to form polymers (Ziegler-Natta polymerization see Section 13.2.4). 

Similar removal of an alcoholic substituent is found in the indophenol color reaction of p-hydroxybenzyl alcohols (XXXIX) with TV-chloro-quinoneimide (Ziegler and Gartler (42, 43), Gierer (20)). If the quinamine type compound (XL) is assumed as an intermediate in this reaction, its decomposition to the indophenol (XLI) and the aldehyde (XLII) (42, 43) would be analogous to the decomposition of XXXII postulated above. 

Applications of HT-type catalysts, prepared by the above methods, have been reported in recent years for basic catalysis (polymerization of alkene oxides, aldol condensation), steam reforming of methane or naphtha, CO hydrogenation as in methanol and higher-alcohol synthesis, conversion of syngas to alkanes and alkenes, hydrogenation of nitrobenzene, oxidation reactions, and as a support for Ziegler-Natta catalysts (Table 2). 

The remaining 30 percent of 1-butene is divided among several uses. About 10-15 percent of the 1-butene is polymerized in the presence of a Ziegler-type catalyst to produce polybutene-1 resin. The markets for this resin are pipe, specialty films, and polymer alloys. Approximately the same volume of 1-butene is reacted with synthesis gas in an oxo reaction to produce valeraldehydes. These C5 aldehydes are then hydrogenated to amyl alcohols or oxidized to valeric acid. Amyl alcohols are consumed in the production of lube oil additives and amyl acetate and in solvent uses. Valeric acid goes into lubricant base stocks and specialty chemicals. 

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