Cyanogen chloride, in preparation

NDRC (1946b) Hydrogen cyanide and cyanogen chloride. In Preparation and evaluation of potential chemical warfare agents. Summary Technical Report of Division 9, NDRC, vol 1, part 1, chapter 2. National Defense Research Committee, Office of Scientific Research and Development, Washington, DC, pp 7-16. 

Preparation. A compd C2F6N2 was reported in 1936 among the prods of the action of F on Ag cyanide (Ref 2), but the structure was not proved until 1940, when it was prepd in good yield by the action of 1 pentafluoride on I cyanide (Ref 4). Since then it has been prepd as the major prod from the action of Ag di-fluoride on cyanogen chloride (Refs 6 10) by the interaction of Cl, Na fluoride, and cyanogen chloride in a sealed tube at 50° for 1 hour (Refs 9 10) and in low yields by the fluori-nation of ethylene diamine or ethyleneimine (Ref 7)... 

I-Cyanobenzocyclobctene, 48, 53 8-Cyanoethylhydrazine, from acrylonitrile and hydrazine, 48, 8 reaction with sulfuric acid, 48, 8 Cyanogen bromide, 45, 88 Cyahogen chloride, in preparation of chlorosulfonyl isocyanate, 46, 24 reaction with sulfur trioxide, 46, 24 7-Cvanoheptanal, 49, 27, 28... 

Caution Cklorosulfonyl isocyanate is highly corrosive and may be contaminated with cyanogen chloride. This preparation should be carried out in a good hood, and rubber gloves should be worn. 

Caution Since cyanogen chloride is highly toxic, the preparation and isolaiion of the sulfonyl cyanide should be condwted in a well-ventilated hood. 

The preparation of chlorosulfonyl isocyanate is described in Org. Syn., Coll. Vol. 5, 226 (1973). This compound is highly corrosive, reacts explosively with water, and may be contaminated with cyanogen chloride. 

Cyanogen chloride, an extremely poisonous gas, is commercially available in cylinders (expensive ). It can be prepared from chlorine and sodium cyanide in carbon tetrachloride [109] (see also p. 156)... 

The formadon of alkynenitriles from alkynylmagnesium halides and cyanogen chloride was described far die fust tune by Grignard [114], A number of these nitriles have been prepared in our laboratory from alkynyllithium and cyanogen chloride using I O as a solvent [115], Cyanogen bromide is unsuitable because the alkynylide attacks on bromine [2],... 

Of the various published methods of preparing phenylurea, such as treatment of aniline salts with potassium cyanate in water solution,1 heating aniline with urea,2 with cyanic acid,3 or with cyanogen chloride,4 and the interaction of phenyl isocyanate or phenylcarbamine chloride with ammonia,5 the only ones to be considered as practical methods for preparation are the first two. The first suffers from the disadvantage that potassium cyanate is not easily prepared in the laboratory and rapidly undergoes spontaneous decomposition in storage while by the action of urea on aniline alone, carbanilide is formed in rather larger proportion than phenylurea. 

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. 

The checkers used cyanogen chloride supplied in a metal cylinder by the American Cyanamid Co., Bound Brook, New Jersey. The submitter prepared cyanogen chloride beforehand1 and either charged it as a liquid or allowed it to distil in as is required later in the reaction.9... 

Before the development of the cyanamide process for the fixation of nitrogen, cyanamide was prepared by the interaction of cyanogen chloride er bromide (from the action of the halogen on potassium cyanide) with ammonia in water or ether solution. 

If the reaction, say, with cyanogen chloride, is carried out in ether solution, ammonium chloride precipitates and is filtered off, and the cyanamide is procured as a syrup by allowing the ether solution to evaporate spontaneously and later as crystals by allowing the syrup to stand over sulfuric acid in a desiccator. Cyanamide may also be prepared by removing the component atoms of hydrogen sulfide from thiourea by means of mercuric oxide. Thionyl chloride effects the corresponding removal of water from urea. 

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