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With sodium cyanide

HOOCCH2CH2CH2COOH. M.p. 97-98 C, b.p. 302-304°C. Prepared by treating 1,3-dichloropropane with sodium cyanide and heating the product with NaOH. Forms an anhydride on heating at 230-280 C. glutathione, glutamylcysteinylglycine, GSH, CioH. NaOfiS. M.p. 190-192 C (decomp.). [Pg.191]

Mandelic acid. This preparation is an example of the synthesis of an a-hydroxy acid by the cyanohydrin method. To avoid the use of the very volatile and extremely poisonous hquid hydrogen cyanide, the cyanohydrin (mandelonitrile) is prepared by treatment of the so um bisulphite addition compound of benzaldehj de (not isolated) with sodium cyanide ... [Pg.754]

Indole (I) condenses with formaldehyde and dimethylamine in the presence of acetie acid (Mannich reaction see Section VI,20) largely in the 3-position to give 3 dimethylaminomethylindole or gramine (II). The latter reaets in hot aqueous ethanol with sodium cyanide to give the nitrile (III) upon boiling the reaction mixture, the nitrile undergoes hydrolysis to yield 3-indoleaeet-amide (IV), part of which is further hydrolysed to 3-indoleacetic acid (V, as sodium salt). The product is a readily separable mixture of 20 per cent, of (IV) and 80 per cent, of (V). [Pg.1012]

When the reaction was earned out m aqueous methanol as the solvent hexyl bromide was converted to hexyl cyanide m 71% yield by heating with sodium cyanide Although this IS a perfectly acceptable synthetic reaction a peiiod of ovei 20 hours was lequued Changing the solvent to dimethyl sulfoxide brought about an increase m the reaction rate... [Pg.347]

The reaction of cyclopentyl bromide with sodium cyanide to give cyclopentyl cyanide... [Pg.362]

Nitdles may be prepared by several methods (1). The first nitrile to be prepared was propionitdle, which was obtained in 1834 by distilling barium ethyl sulfate with potassium cyanide. This is a general preparation of nitriles from sulfonate salts and is referred to as the Pelou2e reaction (2). Although not commonly practiced today, dehydration of amides has been widely used to produce nitriles and was the first commercial synthesis of a nitrile. The reaction of alkyl hahdes with sodium cyanide to produce nitriles (eq. 1) also is a general reaction with wide appHcabiUty ... [Pg.217]

The physical properties of cyanoacetic acid [372-09-8] and two of its ester derivatives are Hsted ia Table 11 (82). The parent acid is a strong organic acid with a dissociation constant at 25°C of 3.36 x 10. It is prepared by the reaction of chloroacetic acid with sodium cyanide. It is hygroscopic and highly soluble ia alcohols and diethyl ether but iasoluble ia both aromatic and aUphatic hydrocarbons. It undergoes typical nitrile and acid reactions but the presence of the nitrile and the carboxyUc acid on the same carbon cause the hydrogens on C-2 to be readily replaced. The resulting malonic acid derivative decarboxylates to a substituted acrylonitrile ... [Pg.225]

Dichloroacetic acid is produced in the laboratory by the reaction of chloral hydrate [302-17-0] with sodium cyanide (31). It has been manufactured by the chlorination of acetic and chloroacetic acids (32), reduction of trichloroacetic acid (33), hydrolysis of pentachloroethane [76-01-7] (34), and hydrolysis of dichloroacetyl chloride. Due to similar boiling points, the separation of dichloroacetic acid from chloroacetic acid is not practical by conventional distillation. However, this separation has been accompHshed by the addition of a eotropeforming hydrocarbons such as bromoben2ene (35) or by distillation of the methyl or ethyl ester. [Pg.89]

Other Reactions. The reaction of Thydioxybenzaldehyde with sodium cyanide and ammonium chloride, Strecker synthesis, yields /J-hydroxyphenylglycine [938-97-6] a key intermediate in the manufacture of semisynthetic penicillins and cephalosporins (see Antibiotics, p-LACTAMs). [Pg.506]

In a fire-assay method used at the smelters, a weighed quantity of concentrate is mixed with sodium cyanide in a clay or porcelain cmcible and heated in a muffle furnace at red heat for 20—25 min. The tin oxide is reduced to metal, which is cleaned and weighed. Preliminary digestion of the concentrate with hydrochloric and nitric acids to remove impurities normally precedes the sodium cyanide fusion. [Pg.60]

Miscellaneous uses for sodium cyanide include heat treating, metal stripping, and compounds used for clearing smut. Treatment of wood chips with sodium cyanide and CaCl2 reportedly increases the kraft cooking yield of pulp (qv) (64). [Pg.384]

Potassium cyanide is primarily used for fine silver plating but is also used for dyes and specialty products (see Electroplating). Electrolytic refining of platinum is carried out in fused potassium cyanide baths, in which a separation from silver is effected. Potassium cyanide is also a component of the electrolyte for the analytical separation of gold, silver, and copper from platinum. It is used with sodium cyanide for nitriding steel and also in mixtures for metal coloring by chemical or electrolytic processes. [Pg.385]

Halogenomethyl, hydroxymethyl and aminomethyl groups readily undergo displacement reactions with nucleophilic reagents. Both side-chain and nuclear substitution products have been obtained (Scheme 57). These two possibilities are exemplified by the reaction of furfuryl chloride with sodium cyanide (Scheme 58). [Pg.70]

Halogeno-l-methyl-l,2,3-triazoles undergo substitution reactions with amines, but the 4-halogeno analogs do not. 5-Chloro-l,4-diphenyl-l,2,3-triazole with sodium cyanide in DMSO gives the cyano derivative (63JCS2032). 1-Substituted 3-chloro- and 5-chloro-l,2,4-triazoles both react with amines. [Pg.105]

Chloro-l,2-benzisothiazole reacts with sodium cyanide to give a mixture containing mainly o-cyanophenyl thiocyanate with some di-(o-cyanophenyl) disulfide. An 80% yield of the latter was obtained using cuprous cyanide in DMF (73SST(2)556). [Pg.152]

This method is particularly applicable to the more reactive benzyl halides which are easily hydrolyzed in the aqueous media usually employed for the metathetical reaction with alkali cyanides. For example, anisyl chloride treated with sodium cyanide in aqueous dioxane gives, as a by-product, 5-10% of anisyl alcohol as determined by infrared analysis. The use of anhydrous acetone not only prevents hydrolysis to the alcohol but also decreases the formation of isonitriles. This method was also applied successfully by the submitters to the preparation of -chlo-rophenylacetonitrile in 74% yield. [Pg.52]

The cyanohydrin of methyl perfluoroheptyl ketone was synthesized by a two-step process addition of sodium bisulfite and subsequent treatment with sodium cyanide. When the ketone was reacted with sodium cyanide, cyclic addition products were obtained, instead of the product of cyanohydrin formation. This result was attributed to the solubility characteristic of a long perfluoroalkyl group, which makes the compound less soluble in water and polar organic solvents [54] (equation 40) (Table 14). [Pg.638]

The thenyl chlorides appear to be more reactive in nucleophilic aliphatic substitution than the benzyl analogs. Thus, 2-thenyh chloride gives, in the reaction with sodium cyanide in ethanol, a mixture of ethyl 2-thenyl ether (25% yield) and 2-thenyl cyanide (32% yield), whereas benzyl chloride gives a high 3deld of benzyl cyanide uncontaminated with benzyl ether. When 2-thenyl chloride and benzyl chloride were allowed to compete for a deficiency of sodium amyloxide, 2-thenyl chloride reacted three times faster. In acetone solution 2-thenyl cyanide is obtained smoothl. ... [Pg.88]

The utility of 2,2 -biindolyl derivatives as indolocarbazole precursors has also been exploited extensively by Somei and co-workers, who reported the first syntheses of the naturally occurring indolo[2,3-a]carbazoles 16 and 17 (Scheme 9). A chloroacetylation of 2,2 -biindolyl (46) followed by treatment of the resulting product 58 with sodium cyanide in formamide-methanol provided 59. Transformation of 59 into the acetoxy derivative 60, followed by hydrolysis to 61, finally led to the target compounds after subsequent sequential melhylations [97H(45)1647]. [Pg.13]

For the in situ preparation of the required arenediazonium salt from an aryl amine by application of the diazotization reaction, an acid HX is used, that corresponds to the halo substituent X to be introduced onto the aromatic ring. Otherwise—e.g. when using HCl/CuBr—a mixture of aryl chloride and aryl bromide will be obtained. The copper-(l) salt 2 (chloride or bromide) is usually prepared by dissolving the appropriate sodium halide in an aqueous solution of copper-(ll) sulfate and then adding sodium hydrogensulfite to reduce copper-(ll) to copper-(1). Copper-(l) cyanide CuCN can be obtained by treatment of copper-(l) chloride with sodium cyanide. [Pg.248]

A thiazole derivative that incorporates a fragment of the amphetamine molecule shows some CNS stimulant activity more specifically, the compound antagonizes the depression caused by overdoses of barbiturates and narcotics. Reaction of benzalde-hyde with sodium cyanide and benzenesulfonyl chloride gives the toluenesulfony1 ester of the cyanohydrin (141). Reaction of this with thiourea leads directly to aminophenazole (143) It is probable the reaction proceeds by displacement of the tosylate by the thiourea sulfur to give 142 addition of the amino group to the nitrile followed by tautomerization affords the observed product. ... [Pg.248]

Mefenidil (78) is a cerebral vasodilator which may be of value in treating geriatric cerebral circulatory problems. It can be synthesized by reacting benzamidine (76) with biacetyl to produce the highly reactive methylene benzimidazole adduct 77. Reaction of the latter with sodium cyanide completes the synthesis 1,26]. [Pg.89]

The 5-methyl-5-ethyloxazolidine-2,4-dione may be prepared by reacting methyl ethyl ketone with sodium cyanide and with ammonium thiocyanate followed by desulfurization. This intermediate may also be prepared by condensing a-hydroxy-a-methylbutyramide with ethyl chlorocarbonate or by condensing ethyl a-hydroxy-a-methylbutyrate with urea. Another method described (Traube and Aschar, Ber., 46, 2077-1913) consists in the condensation of ethyl a-hydroxy-a-methylbutyrate with guanidine followed by hydrolysis. [Pg.1162]

Stereoselective Strecker reactions with galactosylamine 1 can also be achieved with sodium cyanide and acetic acid in 2-propanol. The reactions, however, proceed slowly and with a lower stereoselectivity, giving diastereomeric ratios of the products between 3 1 and 7 1. The scope of the method can be extended to other glycosylamines, e.g., 2,3,4-tri-O-pivaloyl-a-D-arabinosyl-amine which allows the stereoselective synthesis of (A )-amino nitriles61,62. [Pg.794]

Even though the equilibrium constant for the formation of Au3- from gold is very unfavorable, the reaction proceeds because any Au3+ ions formed are immediately complexed by Cl- ions and removed from the equilibrium. In a process widely used in the refining of the metal, gold also reacts with sodium cyanide in an aerated aqueous solution to form the complex ion [Au(CN)2] ... [Pg.787]

The Strecker reaction has been performed on the aldehyde 182 prepared from L-cysteine [86] (Scheme 28). The imine was formed in situ by treatment with benzylamine, then TMS cyanide was added to afford prevalently in almost quantitative yield the syn-diamine 183, which is the precursor of (-l-)-biotin 184. The syn selectivity was largely affected by the solvent, toluene being the solvent of choice. Since the aldehyde 182 is chemically and configurationally unstable, a preferred protocol for the synthesis of 183 involved the prehminary formation of the water-soluble bisulfite adduct 185 and the subsequent treatment with sodium cyanide. Although in this case the syn selectivity was lower, both diastereomers could be transformed to (-l-)-biotin. [Pg.33]


See other pages where With sodium cyanide is mentioned: [Pg.166]    [Pg.259]    [Pg.191]    [Pg.358]    [Pg.785]    [Pg.261]    [Pg.397]    [Pg.395]    [Pg.128]    [Pg.87]    [Pg.162]    [Pg.540]    [Pg.637]    [Pg.358]    [Pg.785]    [Pg.14]    [Pg.270]    [Pg.792]    [Pg.151]   
See also in sourсe #XX -- [ Pg.266 ]




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Alanal, reaction with sodium cyanide

Alkyl bromides, reaction with sodium cyanide

Alumina, impregnated with sodium cyanide

Butyl bromide reaction with sodium cyanide

Butyl bromide with sodium cyanide

Chloromethyl with sodium cyanide

Chlorotrifluoroethylene, reaction with aqueous sodium cyanide to form

Condensation, of acetoacetic ester, acid with sodium cyanide and hydrazine

Cyanide poisoning systemic (with sodium

Furfuryl chloride, reaction with sodium cyanide

Saponification, of an ester with sodium cyanide

Sodium cyanide

Sodium cyanide, reaction with

The Use of Calcium or Barium Salts with Sodium Cyanide

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