Potassium cuprous cyanide

Reaction XLIX. (a) Action of Cuprous Potassium Cyanide on Aromatic Diazonium Compounds. (Sandmeyer). (B., 17, 1633, 2650 18, 1492, 1496.)—If a diazonium salt is added to a hot solution of cuprous-potassium cyanide, and the whole boiled on a water hath, nitrogen is evolved, and the corresponding nitrile formed. (C. r., 183, 421.)... 

The details of this preparation are practically the same as those given for p-tolu-nitrile (Preparation 82). A cuprous-potassium cyanide solution, prepared as therein described, is warmed to about 70°, and added in small portions to a solution of benzene-diazonium chloride prepared from 18-6 gms. (1 mol.) of aniline as described in Preparation 379. When the addition is complete, the liquid is warmed on a water bath for 15 minutes and distilled in steam the distillate is extracted with ether. The ethereal solution is washed repeatedly with dilute caustic soda and with dilute sulphuric acid, dried over anhydrous potassium carbonate, filtered, and the oil which remains on driving off the ether fractionated. Owing to the evolution of cyanogen and hydrocyanic acid, this preparation must be carried out in a good fume cupboard. 

SYNS COPPER(I) POTASSIUM CYANIDE CUPRATE(l-), DICYANO-, POTASSIUM CUPROUS POTASSIUM CYANIDE POTASSIUM COPPER(I) CYANIDE POTASSIUM DICYANOCUPRATE(l-)... 

From Diazo Compounds.—The diazo compounds may also be used as intermediate products to obtain the acid nitriles and thus the acids. The reaction already discussed under diazo compounds (p. 599) is the Gattermann reaction with cuprous potassium cyanide, KCN.CuCN, by which the diazo group is replaced by the cyanogen group. 

Copper(l) potassium cyanide Cuprate(l-), dicyano-, potassium Cuprous potassium cyanide EINECS 237-192-2 Potassium copper(i) cyanide Potassium cuprocyanide Potassium dicyanocuprate Potassium dicyanocuprate(l-) UN1679. A double cyanide of potassium and copper used in electroplating copper and brass. Prisms d = 2.38 insoluble In H2O, soluble In DMSO. 

Potassium cupro-cyanide is the most convenient form in which cuprous cyanide can be used in Sandmeyer s Reaction. It is prepared by adding an excess of potassium cyanide to copper sulphate solution, whereby the cupric cyanide which is formed immediately breaks down to give cuprous cyanide and cyanogen, and the cuprous cyanide then dissolves in the excess of potassium... 

The Sandmeyer reaction may also be applied to the preparation of nitriles. The solution of the diazonium salt is added to a solution of cuprous cyanide in excess of sodium or potassium cyanide solution (sometimes improved yields are obtained by substituting nickel cyanide for cuprous cyanide), for example CH3 CH, CH3... 

Benzonitrile (phenyl cyanide). Prepare a cuprous cyanide solution in a 500 ml. round-bottomed flask as above, but use the following quantities 65 g. of crystallised copper sulphate in 205 ml. of water, 18 g. of sodium bisulphite in 52 ml. of water, and 18 g. of potassium cyanide in... 

In some instances a carbon-carbon bond can be formed with C-nucleophiles. For example, 3-carboxamido-6-methylpyridazine is produced from 3-iodo-6-methylpyridazine by treatment with potassium cyanide in aqueous ethanol and l,3-dimethyl-6-oxo-l,6-dihydro-pyridazine-4-carboxylic acid from 4-chloro-l,3-dimethylpyridazin-6-(lH)-one by reaction with a mixture of cuprous chloride and potassium cyanide. Chloro-substituted pyridazines react with Grignard reagents. For example, 3,4,6-trichloropyridazine reacts with f-butyl-magnesium chloride to give 4-t-butyl-3,5,6-trichloro-l,4-dihydropyridazine (120) and 4,5-di-t-butyl-3,6-dichloro-l,4-dihydropyridazine (121) and both are converted into 4-t-butyl-3,6-dichloropyridazine (122 Scheme 38). 

Allyl cyanide has been found in oil of mustard 1 and has been prepared from allyl chloride and potassium cyanide,2 allyl bromide and potassium cyanide,3 allyl iodide and potassium cyanide4 and silver cyanide.5 The method described in the procedure is essentially that of Bruylants, who has shown that the yields are much better when dry cuprous cyanide is treated with allyl bromide.6... 

Thenoic acid has been prepared in low yield by oxidation of 3-methylthiophene with potassium permanganate,2-4 dilute nitric acid, chromic acid, and hydrogen peroxide,4 and by reductive dechlorination of chloro-3-thenoic acid.4 Starting with 3-iodothiophene, which is difficult to obtain, good yields are obtained by the Grignard procedure 6 or with cuprous cyanide and potassium cyanide in a sealed tube.6... 

The substance is stable at ordinary temperatures and up to 100°C. Like cupric acetylide it decomposes on being heated in hydrochloric acid (Berthelot [102], Sabaneyev [107]). A solution of potassium cyanide also causes decomposition with the loss of acetylene. Makowka [108] showed that aldehyde-like compounds are formed from cuprous acetylide on reaction with a 30% solution of hydrogen peroxide. 

Diazotise 223 g. of 2-naphtliylamine-l-sulphonic acid as detailed under fi-Bromonaphthalene in Section IV,62. Prepare cuprous cyanide from 125 g. of cupric sulphate pentahydrate (Section IV,66) and dissolve it in a solution of 65 g. of potassium cyanide in 500 ml. of water contained in a 1-litre three-necked flask. Cool the potassium cuprocyanide solution in ice, stir mechanically, and add the damp cake of the diazonium compound in small portions whilst maintaining the temperature at 5-8°. Nitrogen is soon evolved and a red precipitate forms gradually. Continue the stirring for about 10 hours in the cold, heat slowly to the boiling point, add 250 g. of potassium chloride, stir, and allow to stand. Collect the orange crystals which separate by suction filtration recrystallise first from water and then from alcohol dry at 100°. The product is almost pure potassium 2-cyanonaphthalene-l-sulphonate. Transfer the product to a 2-litre round-bottomed flask, add a solution prepared from 400 ml. of concentrated sulphuric acid and 400 g. of crushed ice, and heat the mixture under reflux for 12 hours. Collect the -naphthoic acid formed (some of which sublimes from the reaction mixture) by suction filtration... 

Mesitylacetonitrile can be prepared by the action of potassium cyanide on < 2-chloroisodurene4 or by treating a. 2-chloroisodurene with cuprous cyanide in the presence of pyridine.5 The procedure described is based upon the method for the preparation of benzyl cyanide from benzyl chloride. 

Cuprous Cyanide, Cu-(CN), while monnclinic crystals, insoluble in H 0, soluble in HCI. NHjOH. and potassium cyanide. Used in Sandmeyer s reaction to synthesize aryl cyanides. 

Cuprous Iodide, Cu.O. cubic while crystals, practically insoluble in H 0 or alcohol, soluble in NHjOH. potassium iodide, or potassium cyanide. Used in Sandmeyer s reaction lo synthesize aryl chlorides. Cupric Oxide. CuO, black cubic crystals, insoluble in IFO. soluble in HCI. NHjOH. or ammonium chloride. Used as a green and blue colorant in ceramics. 

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