Cyanoethyl ethers

Small amounts of propionitrile and bis(cyanoethyl) ether are formed as by-products. The hydrogen ions are formed from water at the anode and pass to the cathode through a membrane. The catholyte that is continuously recirculated in the cell consists of a mixture of acrylonitrile, water, and a tetraalkylammonium salt the anolyte is recirculated aqueous sulfuric acid. A quantity of catholyte is continuously removed for recovery of adiponitrile and unreacted acrylonitrile the latter is fed back to the catholyte with fresh acrylonitrile. Oxygen that is produced at the anodes is vented and water is added to the circulating anolyte to replace the water that is lost through electrolysis. The operating temperature of the cell is ca 50—60°C. Current densities are 0.25-1.5 A/cm (see Electrochemical processing). 

Reaction of olefin oxides (epoxides) to produce poly(oxyalkylene) ether derivatives is the etherification of polyols of greatest commercial importance. Epoxides used include ethylene oxide, propylene oxide, and epichl orohydrin. The products of oxyalkylation have the same number of hydroxyl groups per mole as the starting polyol. Examples include the poly(oxypropylene) ethers of sorbitol (130) and lactitol (131), usually formed in the presence of an alkaline catalyst such as potassium hydroxide. Reaction of epichl orohydrin and isosorbide leads to the bisglycidyl ether (132). A polysubstituted carboxyethyl ether of mannitol has been obtained by the interaction of mannitol with acrylonitrile followed by hydrolysis of the intermediate cyanoethyl ether (133). 

On treatment with acrylonitrile in 2% aqueous sodium hydroxide at 0°, tetrahydropyran-2-yl /3-D-glucopyranoside gave the 2-, 3-, 4-, and 6-0-(2-cyanoethyl) ethers (together with some diethers) in yields that, on extrapolation to zero reaction, showed3 9 k2 k3 k4 k6 to be in the ratios of 3 1 2 8 these values represent equilibrium, not rate, constants. The tendency for substitution at 0-6 is a consequence of the greater stability of an ether derived from a primary (compared to a secondary) hydroxyl group, as a result of lower steric interactions in the former. 

In this connexion ethyl 2-cyanoethyl ether, EtO-[CH2]2-CN, was tested and found to be relatively non-toxic, showing that the toxicity of the fluorine analogue was caused ultimately by the presence of the fluorine atom (as fluoroethoxyl) and not to any extent by another part of the molecule. 

PHENYLENEDIAMINE p-PHENYLENEDIAMINE PHENYLHYDRAZINE BIS(CYANOETHYL)ETHER DIMETHYL MALEATE ASCORBIC ACID CITRIC ACID... 

The condensable products were analyzed by gas-liquid chromatography using columns containing either l,2,3-tris(2-cyanoethoxy) -propane or di-2-cyanoethyl ether supported on Embacel. Hydrocarbons were determined on columns containing either dimethylsulfolane or a combination of propylene carbonate, squalene, and silicone oil on Embacel (3). 

Many other ethers of carbohydrates have been prepared and described among these the more common additional ones are the following ethyl, benzyl, hydroxymethyl, hydroxyethyl, allyl, and cyanoethyl ethers. In the vast majority of the cases complete or nearly complete substitution of the hydroxyl groups was effected. In other instances partial substitution was obtained, but often little or no information was supplied concerning the location of substituents. Investigations of these types will be mentioned briefly, in order mainly to indicate the extent of the information that is available. 

The 2-cyanoethyl ethers of varying degrees of substitution of a guar galactomannan were subjected to periodate oxidation.88 The results that were obtained are indicative of a random distribution of the cyano-ethyl grouping. 

The example discussed in the next section is one of intermediate complexity (anodic oxidation of /i-cyanoethyl ethers). A simpler example would not give the flavor of a real investigation. 

Wermeckes and Beck examined the anodic oxidation of /f-cyanoethyl ethers, ROCH2CH2CN (R = Me, Et, f-Bu, CH2CH2CN), at Pt and Pb02 electrodes in 1.6 M... 

Experiments on the mechanism of the oxidation of /t-cyanoethyl ethers were carried out by Wermeckes and Beck in both a one-compartment and a two-compartment cell. In the electrolysis of ethylpropionitrile (EPN) there is an early appearance of / -oxypropionitrile, which is an intermediate in the formation of NCCH2CH2OCH2CH2CN and acetaldehyde. Evidently Et is being attacked at the CH2 group to give a hemiacetal in a two-electron oxidation (Fig. 11.1). This is split in solution to yield the intermediates mentioned. HCN is found as a side product, and it may come from an anodic attack on the CH2 next to the cyano group. Cyanohydrin would be formed, and this is readily saponified. Wermeckes and Beck made sure that the cleavage of the C-0 bond occurs only under anodic electrochemical conditions, that is, that it is not a solution reaction. 

Fig. 11.3. Wermeckes and Beck s reaction mechanism for the anodic oxidation of the / -cyanoethyl ether EPN to the main products Hac and CEA. (Reprinted from B. Wermeckes and F. Beck, Electrochim. Acta 30 1491, copyright 1985, with permission from Elsevier Science.)...

Alanine has been prepared by the catalytic reduction of cyanoacetic esters 1 or salts 2 by heating acrylonitrile,3 /3-amino-propionitrile,4 f>M-(/3-cyanoethyl)-amine,5/3-hydroxypropionitrile, /3-alkoxypropionitriles,7 foV(/3-cyanoethyl) ether,8 or 6is-(/3-cyano-ethyl) sulfide 8 with aqueous ammonia at 150-225° by the hydrolysis of /3-aminopropionitrile with concentrated hydrochloric acid and subsequent removal of the acid with anion exchange resins.9 The method as described above has been published.10 Additional references to methods of preparation are given in connection with a procedure for the making of /3-alanine from suc-cinimide through the action of potassium hypobromite.11... 

C6H8N20 bis(cyanoethyl) ether 1656-48-0 1.038E-h10 74.020 8881 C6H14 3-methylpentane 96-14-0 9.630E-t-09 68.250... 

The first sodium amalgam-induced dimerization of acrylonitrile to adiponitrile [29] was performed in aqueous solution, and the yield was discouragingly low (5%). Mainly, a base-induced addition of water resulting in p, -bis(cyanoethyl) ether occurred together with a reduction to propionitrile (PN). 

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