Cuprous chloride acrylonitrile

Kurtz A process for making acrylonitrile by reacting hydrogen cyanide with acetylene in the presence of aqueous cuprous chloride. Invented by R Kurtz at I. G. Farbenindustrie in the 1940s. The process was widely used, but by 1970 had been abandoned in the United States in favor of the ammoxidation processes. 

Copper chloride complexes can be used as catalysts in a number of organic reactions. Examples include the Wacker process, which is the oxidization of ethylene to acetaldehyde by oxygen and aqueous Cu and Pd precatalysts (or, alternatively using iron catalysts) plus the synthesis of acrylonitrile from acetylene and hydrogen cyanide using CuCl. Cuprous chloride has also been used as a desulfiuizmg and... 

Hydrogen cyanide can also be added direcdy to acetylene, the most successful method being to pass the two gases through an aqueous solution of cuprous chloride and ammonium chloride at 80°C. The dilute solution of acrylonitrile obtained in this way is concentrated by continuous distillation ... 

It was once widely used to make acrylonitrile by reaction with acetylene in presence of an aqueous cuprous chloride-ammonium chloride catalyst, but this process is obsolescent and is being displaced by ammoxidation of propene with bismuth molybdate catalysts ... 

Detailed Examination of the Sandmeyer Reaction A. All mixtures contained 6 ml. of acrylonitrile in 100 ml. of O.IAT hydrochloric acid containing O.OliV cuprous chloride. 

The acetylene process was developed in Germany in the early 1940s to supply the synthetic rubber industry [19]. Acetylene is reacted with hydrogen cyanide in an aqueous medium in the presence of catalytic amounts of cuprous chloride. The reaction is maintained at 80 90°C at a pressure of 1-2 atm. The reaction is highly exothermic forming a gaseous reactor effluent. This crude product is water-scrubbed and the pure acrylonitrile product is recovered from the resultant 1-3% aqueous solution by fractional distillation. The major drawbacks of this process are the large number of by-products formed by hydration, the loss of catalyst activity from hydrolysis reactions, and the buildup of ammonium chloride and tars. 

A second commercial route to acrylonitrile used by DuPont, American Cyanamid, and Monsanto was the catalytic addition of HCN to acetylene (46). The reaction occurs by passing HCN and a 10 1 excess of acetylene into dilute HCl at 80° C in the presence of cuprous chloride as the catalyst. These processes use expensive C2 hydrocarbons as feedstocks and thus have higher overall acrylonitrile production costs compared to the propylene-based process technology. The last commercial plants using these process technologies were shutdown by 1970. 

Direction of addition. A mixture of methyldichlorosilane, acrylonitrile, and a 3-component catalyst system consisting of cuprous chloride, tri-n-butylamine, and N,N,N, N -tetramethylethylenediamine refluxed 40 hrs. while the temp, rises from 51 to over 126° j -cyanoethylmethyldichlorosilane. Y 79%.—The above catalyst system favors the formation of y -adducts. F. e. s. B. A. Bluestein, Am. Soc. 83, 1000 (1961). 

In the presence of such catalysts as a solution of cuprous and ammonium chlorides, hydrogen cyanide adds to acetylene to give acrylonitrile... 

In the presence of such catalysts as a solution of cuprous and ammonium chlorides, hydrogen cyanide adds to acetylene to give acrylonitrile (CH2=CHCN). However, this process has been replaced by processes involving ammoxidation of propylene. Similarly, the process for the manufacture of acrylic acid has been superseded by processes involving oxidation of propylene (Fig. 1) although, for some countries, acetylene may still be used in acrylate manufacture. 

Several complexes of cuprous halides with acrylonitrile 69> and acrolein 70> have been investigated. The enthalpies of complexing have been found from vapour pressure measurements the enthalpy of formation of the complex from solid copper chloride and liquid acrylonitrile was -29.3 kJ mole-1, while with copper bromide this was -1.3 kJ mole-1. The corresponding value for the acrolein complex was -17.3 kJ mole-1 the enthalpy values for the formation from the gaseous olefinic compounds were -62.3, -34.3 and -49.2 kJ mole-1 respectively. 

Cuprous methyltrialkylborates (54), which are prepared from trialkylboranes, methyl lithium and cuprous halide, are useful alkylating agents. Reaction with acrylonitrile for example gave the corresponding 1,4-adducts which are converted into alkyl cyanides by hydrolysis (Scheme 6). Yields are generally excellent, provided cuprous bromide is used and not the chloride or iodide. The complex (54) also reacts readily with 1-acyl-2-vinylcyclopropane to form 1,6-adducts which are hydrolysed to the corresponding /raws -y.S-unsaturated ketone (55) in good yield. 

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