Potassium cupric chloride, preparation

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... 

Catalysts are usually prepared on a large scale by impregnating a suitable alumina support with aqueous solutions of cupric chloride and potassium chloride. Other alkaU metals or rare earth chlorides have been used as promoters or to inhibit by-product formation. 

Thallium(III), particularly as the trifluoroacetate salt, is also a reactive electrophilic metallating species, and a variety of synthetic schemes based on arylthallium intermediates have been devised.75 Arylthallium compounds are converted to chlorides or bromides by reaction with the appropriate cupric halide.76 Reaction with potassium iodide gives aryl iodides.77 Fluorides are prepared by successive treatment with potassium fluoride and boron trifluoride.78 Procedures for converting arylthallium compounds to nitriles and phenols have also been described.79... 

Cuprous cyanide, CuCN.—Addition of potassium cyanide to a solution of cuprous chloride in hydrochloric acid precipitates cuprous cyanide.10 The best method for its preparation is to mix cold aqueous solutions of potassium cyanide (65 grams) and cupric sulphate (130 grams), and expel cyanogen by warming the mixture under an efficient air-extractor. After settling, the cuprous cyanide is decanted, and washed with water, alcohol, and ether.u References to other methods of preparation, and to Sandmeyer s process for aromatic nitriles, are appended.12... 

Preparation. The precursor, l-chloro-4- o-nitrophenyl)-2-butene (3), is prepared by the Meerwein reaction of diazotized o-nitroaniline (2) with butadiene in acetone in the presence of cupric chloride and sodium acetate. - Dehydrohalogenation with methanolic potassium hydroxide then gives the diene (4). ... 

Singh published details of the preparation of cuprous azide from cuprous chloride dissolved in saturated aqueous sodium chloride in presence of a small amount of potassium bisulfite and acidified by acetic acid. The cuprous azide was precipitated by addition of aqueous sodium azide [76,110]. Another way of preparing CuNs is based on the reaction of freshly prepared cuprous oxide (from cupric hydroxide and... 

Preparation by hydrolysis of o-acetoxy-a-acetoxy-acetophenone (SM) with aqueous potassium hydroxide solution by gently wanning for 10-15 min on a water bath maintained at 80° (71%). SM was obtained by cupric chloride-catalyzed decomposition of o-acetoxy-a-diazoacetophenone in dioxane solution in the presence of acetic acid (65%, m.p. 161-162°) [5137]. 

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