Potassium cyanide, reaction with

Potassium cyanide, reaction with N,N-dimethylaminomethyl ferrocene methiodide to yield ferrocenyl-acetonitrile, 40, 45... 

The reaction is a sensitive one, but is subject to a number of interferences. The solution must be free from large amounts of lead, thallium (I), copper, tin, arsenic, antimony, gold, silver, platinum, and palladium, and from elements in sufficient quantity to colour the solution, e.g. nickel. Metals giving insoluble iodides must be absent, or present in amounts not yielding a precipitate. Substances which liberate iodine from potassium iodide interfere, for example iron(III) the latter should be reduced with sulphurous acid and the excess of gas boiled off, or by a 30 per cent solution of hypophosphorous acid. Chloride ion reduces the intensity of the bismuth colour. Separation of bismuth from copper can be effected by extraction of the bismuth as dithizonate by treatment in ammoniacal potassium cyanide solution with a 0.1 per cent solution of dithizone in chloroform if lead is present, shaking of the chloroform solution of lead and bismuth dithizonates with a buffer solution of pH 3.4 results in the lead alone passing into the aqueous phase. The bismuth complex is soluble in a pentan-l-ol-ethyl acetate mixture, and this fact can be utilised for the determination in the presence of coloured ions, such as nickel, cobalt, chromium, and uranium. 

A number of other useful modifications of the intramolecular Williamson synthesis have been developed. Reaction of a,a-dialkyl-/3-tosyloxy aldehydes and ketones with potassium cyanide or with sodium alkoxide gives the corresponding 2-cyano- or 2-alkoxy-oxetanes... 

When labeled potassium cyanide reacted with the complex in an aqueous methanol solution, the bromide was rapidly replaced and the labeled cyanide ion entered slowly into the coordination complex. When the reaction was conducted at higher temperatures in ethylene glycol dimethyl ether as the solvent, the label was distributed among the benzyl isonitrile, benzyl formamide, and the polymer resulting from benzyl isonitrile and the iron isonitrile complexes. 

The free ligand 10a was regenerated by treating 11b with an access of potassium cyanide. Reaction of 10 a with CODPdClMe afforded the chloromethyl palladium complex Ila. In square planar PAN chloromethyl palladium complexes two... 

Potassium cyanide, KCN, is a cyanide salt that is found as a white, amorphous, deliquescent lump or crystalline mass with a faint odor of bitter almonds. It is soluble in water and has a speciflc gravity of 1.52. It is a poison that is absorbed through the skin. Target organs are the same as for sodium cyanide. Reaction with acids releases flammable and toxic hydrogen cyanide gas. The four-digit UN identification number is 1680. The NFPA 704 designation is health 3, flammability 0, and reactivity... 

Multiple labelling with both stable and radioactive isotopes offers the advantage of simultaneous labelling in the same position of a molecule [68]. The combination of C- and C-labelling combines ease of detection with rapid structural identification. The adoption of this technique in studies of some aspects of the metabolism of 4-morpholino-2-piperazinothieno [3,2-d] pyrimidine (V-K 774) (3) in the rat has been reported [69]. Potassium [ C, C]thiocyanate was prepared from a mixture of potassium [ C, C]cyanides. Reaction with ethyl bromide and methyl 3-aminothiophen-2-carboxylate (4) afforded the thienopyri-midine (5), which, by a series of reactions was converted to V-K 774 (3) labelled in the position shown. 

The most important reaction of the sulphonic acids is their conversion into phenols by fusion with caustic alkalis. When they are fused with potassium cyanide, nitriles are obtained, e.g. benzonitriie from ben-zenesulphonic acid. 

Strictly speaking the alkyl halides are esters of the halogen acids, but since they enter into many reactions (t.g., formation of Grignard reagents, reaction with potassium cyanide to yield nitriles, etc.) which cannot be brought about by the other eaters, the alkyl halides are usually distinguished from the esters of the other inorganic acids. The preparation of a number of these is described below. 

Equip a 1-litre three-necked flask with a mechanical stirrer, a separatory funnel and a thermometer. Place a solution of 47 g. of sodium cyanide (or 62 g. of potassium cyanide) in 200 ml. of water in the flask, and introduce 58 g. (73-5 ml.) of pure acetone. Add slowly from the separatory fumiel, with constant stirring, 334 g. (275 ml.) of 30 per cent, sulphuric acid by weight. Do not allow the temperature to rise above 15-20° add crushed ice, if necessary, to the mixture by momentarily removing the thermometer. After all the acid has been added continue the stirring for 15 minutes. Extract the reaction mixture with three 50 ml. portions of ether, dry the ethereal extracts with anhydrous sodium or magnesium sulphate, remove most of the ether on a water bath and distil the residue rapidly under diminished pressure. The acetone cyanohydrin passes over at 80-82°/15 mm. The yield is 62 g. 

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