Catalyst sodium cyanide

Aryl halides reaction with metal cyanides, often with another transition metal catalyst, to give aryl nitriles (aryl cyanides). Aryl halides react with Zn(CN)2 and a palladium catalyst, for example, to give the aryl nitrile. Similarly, aryl iodides react with CuCN and a palladium catalyst to give the aryl nitrile. Potassium cyanide (KCN) reacts in a similar manner with a palladium catalyst. " Sodium cyanide has been used with a copper catalyst and 20% The reaction of aryl iodides... 

Sodium cyanide does not dissolve m butyl bromide The two reactants contact each other only at the surface of the solid sodium cyanide and the rate of reaction under these con ditions IS too slow to be of synthetic value Dissolving the sodium cyanide m water is of little help because butyl bromide is not soluble m water and reaction can occur only at the interface between the two phases Adding a small amount of benzyltrimethyl ammonium chlonde however causes pentanemtnle to form rapidly even at room temper ature The quaternary ammonium salt is acting as a catalyst it increases the reaction rate How7... 

In a related process, 1,4-dichlorobutene was produced by direct vapor-phase chlorination of butadiene at 160—250°C. The 1,4-dichlorobutenes reacted with aqueous sodium cyanide in the presence of copper catalysts to produce the isomeric 1,4-dicyanobutenes yields were as high as 95% (58). The by-product NaCl could be recovered for reconversion to Na and CI2 via electrolysis. Adiponitrile was produced by the hydrogenation of the dicyanobutenes over a palladium catalyst in either the vapor phase or the Hquid phase (59,60). The yield in either case was 95% or better. This process is no longer practiced by DuPont in favor of the more economically attractive process described below. 

Miscellaneous Reactions. Sodium bisulfite adds to acetaldehyde to form a white crystalline addition compound, insoluble in ethyl alcohol and ether. This bisulfite addition compound is frequendy used to isolate and purify acetaldehyde, which may be regenerated with dilute acid. Hydrocyanic acid adds to acetaldehyde in the presence of an alkaU catalyst to form cyanohydrin the cyanohydrin may also be prepared from sodium cyanide and the bisulfite addition compound. Acrylonittile [107-13-1] (qv) can be made from acetaldehyde and hydrocyanic acid by heating the cyanohydrin that is formed to 600—700°C (77). Alanine [302-72-7] can be prepared by the reaction of an ammonium salt and an alkaU metal cyanide with acetaldehyde this is a general method for the preparation of a-amino acids called the Strecker amino acids synthesis. Grignard reagents add readily to acetaldehyde, the final product being a secondary alcohol. Thioacetaldehyde [2765-04-0] is formed by reaction of acetaldehyde with hydrogen sulfide thioacetaldehyde polymerizes readily to the trimer. 

In the early versions, ethylene cyanohydrin was obtained from ethylene chlorohydrin and sodium cyanide. In later versions, ethylene oxide (from the dkect catalytic oxidation of ethylene) reacted with hydrogen cyanide in the presence of a base catalyst to give ethylene cyanohydrin. This was hydrolyzed and converted to acryhc acid and by-product ammonium acid sulfate by treatment with about 85% sulfuric acid. 

Reactions of the Side Chain. Benzyl chloride is hydrolyzed slowly by boiling water and more rapidly at elevated temperature and pressure in the presence of alkaHes (11). Reaction with aqueous sodium cyanide, preferably in the presence of a quaternary ammonium chloride, produces phenylacetonitrile [140-29-4] in high yield (12). The presence of a lower molecular-weight alcohol gives faster rates and higher yields. In the presence of suitable catalysts benzyl chloride reacts with carbon monoxide to produce phenylacetic acid [103-82-2] (13—15). With different catalyst systems in the presence of calcium hydroxide, double carbonylation to phenylpymvic acid [156-06-9] occurs (16). Benzyl esters are formed by heating benzyl chloride with the sodium salts of acids benzyl ethers by reaction with sodium alkoxides. The ease of ether formation is improved by the use of phase-transfer catalysts (17) (see Catalysis, phase-thansfer). 

Many reactions can be carried out between potassium cyanide and organic compounds with the alkalinity of the KCN acting as a catalyst these reactions are analogous to reactions of sodium cyanide. The reactions of potassium cyanide with sulfur and sulfur compounds are also analogous to those of sodium cyanide. Potassium cyanide is reduced to potassium metal and carbon by heating it out of contact with air in the presence of powdered magnesium. Magnesium is converted to the nitride ... 

Hydrogen cyanide is a reactant in the production of acrylonitrile, methyl methacrylates (from acetone), adiponitrile, and sodium cyanide. It is also used to make oxamide, a long-lived fertilizer that releases nitrogen steadily over the vegetation period. Oxamide is produced by the reaction of hydrogen cyanide with water and oxygen using a copper nitrate catalyst at about 70°C and atmospheric pressure ... 

To a solution of l. 47 g (0.03 mol) of sodium cyanide and 4.73 g (0.03 mol) of (-)-(.S)-x-methylbenzylamine hydrochloride in 5 mL of cold water is added 1 g (8.3 mmol) of free ( - )-(.S )-a-mcthylbcnzylaininc in 200 mL of CHjOH. 1.32 g (0.03 mol) of acetaldehyde is added at 0°C and the clear solution is kept at r.t. for five days. After evaporation of the solvent in vacuo, the residue is dissolved in 50 mL of 1 N HC1 and the solution is extracted twice with diethyl ether. After addition of 12 N HCl to adjust the acid concentration to approximately 5 N, the solution is retluxed for 6 h. The HCl is evaporated in vacuo and the residue is dried over sodium hydroxide. The crude. V-x-methylbenzylalaninc hydrochloride is dissolved in 200 mL of 50% ethanol and the pH is adjusted to 6.0 with NaHCOj. To this solution, 3.5 g of palladium hydroxide is added. After hydrogenolysis for 10 h, the catalyst is filtered off and washed with hot water. The filtrate is concentrated to 30%, and the pH is adjusted to 1 with dilute IIC1. The solution is evaporated to dryness and the alanine hydrochloride is extracted with three 20-inL portions of absolute ethanol. After cooling overnight at — 50°C, the precipitated salt is filtered. Pyridine is added to the alcoholic solution to precipitate crude alanine, which is dissolved in 2.5 mL of water. The pH is adjusted with pyridine to 5.5-6.0, and 10 mL of absolute ethanol arc added yield 0.45 g (17% over four steps) mp 290 C [a] 7 + 13.13 (0 = 2.32. 6 N IICi). 

Similarly, Pd/tppts was used by Hoechst (Kohlpainter and Beller, 1997) as the catalyst in the synthesis of phenylacetic acid by biphasic carbonylation of benzyl chloride (Fig. 2.29). The new process replaces a classical synthesis by reaction of benzyl chloride with sodium cyanide, followed by hydrolysis of the resulting benzyl cyanide. Although the new process produces one equivalent of sodium chloride, this is substantially less salt production than in the original process. Moreover, sodium cyanide is about seven times as expensive per kg as carbon monoxide. 

The reaction can be run in an open flask because only a small amount of gas escapes. See Note 3. Sodium cyanide can be substituted for potassium cyanide if 2 g. of jS-alanine is also employed as a catalyst. 

The simplest C-C bond formation reaction is the nucleophilic displacement of a halide ion from a haloalkane by the cyanide ion. This was one of the first reactions for which the kinetics under phase-transfer catalysed conditions was investigated and patented [l-3] and is widely used [e.g. 4-12], The reaction has been the subject of a large number of patents and it is frequently used as a standard reaction for the assessment of the effectiveness of the catalyst. Although the majority of reactions are conducted under liquiddiquid two-phase conditions, it has also been conducted under solidrliquid two-phase conditions [13] but, as with many other reactions carried out under such conditions, a trace of water is necessary for optimum success. Triphase catalysis [14] and use of the preformed quaternary ammonium cyanide [e.g. 15] have also been applied to the conversion of haloalkanes into the corresponding nitriles. Polymer-bound chloroalkanes react with sodium cyanide and cyanoalkanes under phase-transfer catalytic conditions [16],... 

In a sequential continuous process, alcohols are converted initially into the corresponding chloroalkanes, which are flushed without isolation into an aqueous mixture of sodium cyanide and the quaternary ammonium catalyst to produce nitriles [17]. 

Tetra-n-butylammonium cyanide is a better catalyst for benzoin condensation reactions than is sodium cyanide, and >70% yields are obtained under mild conditions [63, 64] tetra-ethylammonium cyanide is less effective. Polymer-supported ammonium catalysts have also been used to promote the benzoin reaction and, although yields are only moderate (40-60%), the convenience of removal of the catalyst is an advantage. Use of chiral ammonium groups produces an enantiomeric excess of chiral products from the condensation of benzaldehyde, but furfural tends to produce a racemate [65]. 

Asymmetric induction using catalytic amounts of quininium or A-methyl-ephedrinium salts for the Darzen s reaction of aldehydes and ketones with phenacyl halides and chloromethylsulphones produces oxiranes of low optical purity [3, 24, 25]. The chiral catalyst appears to have little more effect than non-chiral catalysts (Section 12.1). Similarly, the catalysed reaction of sodium cyanide with a-bromo-ketones produces epoxynitriles of only low optical purity [3]. The claimed 67% ee for the phenyloxirane derived from the reaction of benzaldehyde with trimethylsul-phonium iodide under basic conditions [26] in the presence of A,A-dimethyle-phedrinium chloride was later retracted [27] the product was contaminated with the 2-methyl-3-phenyloxirane from the degradation of the catalyst. 

Other classic examples illustrating the use of quaternary salts as phase transfer catalysts were published by Makosza(2), and by Brandstrom(3). Subsequent development of crown ethers(4-7) and crvptands(7-8) as phase transfer catalysts gave PTC an entirely new dimension since now the inorganic reagent, as sodium cyanide in the above equation, need no longer be dissolved in water but can be used... 

In an extension of this work, the reuse of the polymeric catalyst was addressed and several new PE-poly(alkene) glycol copolymers were prepared [68]. Commercially available oxidized polyethylene (CO2H terminated, both high and low molecular weight) was converted to the acid chloride and reacted with Jeffamine D or Jeffamine EDR, and subsequently converted to the tributylammonium bromide salt with butyl bromide. These new quaternary salts were shown to catalyze the nucleophihc substitution of 1,6-dibromohexane with sodium cyanide or sodium iodide. While none of the polymeric quaternary salts catalyzed the reaction as well as tetrabutylammonium bromide, the temperature-dependent solubility of the polymers allowed removal of the polymer by simple filtration. 

The above hydrochloride is treated with thionyl chloride in liquid sulfur dioxide, to produce an amorphous chloride hydro chloride, which is converted to the nitrile with sodium cyanide in liquid hydrogen cyanide, Methanolysis then gives the ester of the nitrile. Alkaline hydrolysis of this last compound, followed by catalytic dehydrogenation in water using a deactivated Raney Nickle catalyst (see JOC, 13, 455 1948) gives dl-lysergic acid. 

Polymer phase-transfer catalysts (also referred to as triphase catalysts) are useful in bringing about reaction between a water-soluble reactant and a water-insoluble reactant [Akelah and Sherrington, 1983 Ford and Tomoi, 1984 Regen, 1979 Tomoi and Ford, 1988], Polymer phase transfer catalysts (usually insoluble) act as the meeting place for two immiscible reactants. For example, the reaction between sodium cyanide (aqueous phase) and 1-bromooctane (organic phase) proceeds at an accelerated rate in the presence of polymeric quaternary ammonium salts such as XXXIX [Regen, 1975, 1976]. Besides the ammonium salts, polymeric phosphonium salts, crown ethers and cryptates, polyethylene oxide), and quaternized polyethylenimine have been studied as phase-transfer catalysts [Hirao et al., 1978 Ishiwatari et al., 1980 Molinari et al., 1977 Tundo, 1978]. 

Copper(l) cyanide is used in copper plating of nickel, chromium, zinc alloys, steel, and other metals or alloys. Such copper plating imparts brightness, smoothness, hardness, and strength. The cyanide solution employed for copper electroplating consists of copper cyanide and sodium cyanide. Other apph-cations of this compound are as an insecticide, a catalyst in polmerization, and as an antifouling agent in marine paints. 

Substrate selectivities in reactions of aqueous sodium cyanide with alkyl halides in toluene and 17% RS onium ion catalysts are shown in Table 1 84). The data are particularly instructive about how intraparticle diffusion affects reactions that occur... 

Both alumina and silica gel are more stable physically than the common polystyrene supports. The alumina-bound catalysts are particularly promising because of their higher activity and higher selectivity compared with the silica gel-bound catalysts. Alumina also is stable in alkali. The alumina-bound catalysts 32 and 33 worked well for reaction of 1-bromooctane with concentrated aqueous sodium cyanide 118). 

Owing to a sufficient reactivity of the secondary halogen atoms towards nucleophiles, the telomers 421 (n = 1) have also been transformed286 into tetroses. Reaction of 430 with sodium cyanide, induced by a phase-transfer catalyst, afforded trans-438 and ci.s-439 nitriles in... 

To a flask equipped with two dropping funnels and containing 2 liters of saturated sodium chloride solution, 50.0 gm (0.51 mole) of cuprous chloride, 2.0 gm of copper powder, and 50 ml of concentrated hydrochloric acid warmed to 75°C is added a 30% sodium cyanide solution until the pH approaches approximately 3-4. At this time 150.0 gm (2.0 mole) of propargyl chloride is added dropwise over a 4-hr period. At the same time, more of the aqueous 30 % sodium cyanide is added to keep the pH constant at 3-4. The reaction product is later steam-distilled from the catalyst solution, separated from the water, dried, and fractionally distilled to afford 96.0 gm (73 %), b.p. 60°-67°C (95 mm), n ° 1.44-1.45. This product is contaminated with propargyl cyanide and is refractionated to afford pure cyanoallene, b.p. 50°-51.5°C (50 mm), d° 1.4612, Amax 46,500 cm 1, emax 14,200 (methanol). 

Heterocyclic amines have also been used as phase transfer catalysts. However, because these amines quaternize easily, the question is whether the operative catalyst is the tertiary amine or the quaternary ammonium salt formed in situ Furukawa et al.286 have shown that a methyl 2-pyridyl sulfoxide may be used as a phase transfer catalyst and promote substitution reactions between lithium chloride or sodium cyanide and benzyl bromide. According to the authors, the catalyst behaves as a cation complexer and not as a quaternary ammonium salt formed in situ by a Menschutkin reaction. 

Reeves and Hilbrich288 have reported the catalysis by pyridines of benzyl ketone alkylation they are less efficient than aliphatic trialkylamines. Reeves and White289 have also described the reaction of alkyl bromides with sodium cyanide, where pyrazine is a better catalyst (99% yield) compared to pyridine (12% yield). Isakawa et al.289 have also carried out addition of dichloro-carbene to cyclohexene under biphasic conditions, using heterocyclic amines as catalysts (e.g., iV-butylpiperidine gives 76% yield). 

As reported before, the reaction can be carried out in ethanol by adding quickly a stoichiometric quantity of NaCN after the catalyst and aryl halide additions. In methanol or in dimethylformamide the catalytic cyanation occurs only if the sodium cyanide is added slowly. In benzene, always in the presence of NaCN, the reaction does not occur and complexes 1 can be isolated. 

---