Cacodyl cyanide

Bunsen, Robert W. von( 1811-1899). A Ger chemist noted for gasometric and photometric researches and for various inventions, such as burner, valve, cell, clamp funnel eudiometer. The first theory of the burning process of black powder was estabilished by him and simultaneously by a Russian chemist, L. Shishkoff. Bunsen lost the sight of his right eye due to the expln of cacodyl Cyanide, which he discovered together with other derivs of cacodyi... 

CH3)2As.CN crysts, mp 36.5-37.5°. This extremely toxic compd was first prepd by Bunsen(Ref 1). Expln of cacodyl cyanide cost Bunsen the sight of his right eye(Ref 2)... 

The cacodyl radical [(CH3)2As] also appeared to Bunsen to be a stable superatom that could be exchanged amongst other radicals. Many cacodyl compounds are explosive as well as spontaneously flammable. One of these, cacodyl cyanide [(CH3)2AsCN], exploded during Bunsen s exploratory studies, and he lost his right eye. ... 

During the Crimean War, there were several proposals to initiate chemical warfare to assist the Allies, particularly to solve the stalemate during the siege of Sevastopol. In 1854, Lyon Playfair, a British chemist, proposed a cacodyl cyanide artillery shell for use primarily against enemy ships. The British Ordnance Department rejected the proposal as bad a mode of warfare as poisoning the wells of the enemy. 4(p22) Playfair s response outlined a different concept, which was used to justify chemical warfare into the next century ... 

The search was now on to identify different radicals. Dumas found the methyl radical. Robert Wilhelm Bunsen investigated compounds of the cacodyl radical (a smelly, toxic, sometimes explosive set of compounds containing arsenic) and isolated what appeared to be a free radical. It was actually a compound made of two radicals joined together, but it supported the idea that radicals were stable, isolatable entities, which could be treated like organic elements. Bunsen did not carry this work further because an explosion of cacodyl cyanide cost him an eye and several weeks of illness (and thereafter he steered clear of organic chemistry in general). He did go on to have a successful career in other chemical endeavors, inventing for instance a gas burner called the Bunsen burner, which is still standard laboratory equipment. 

British chemist Lyon Playfair proposes that artillery shells be filled with cacodyl cyanide as a way to help British and French forces to capture Sevastopol from the Russians. The proposal is rejected. 

Sodium Hydrosulfide Solution Sodium Bisulfite Sodium Borate Sodium Borohydride Sodium Cacodylate Hexadecyl Sulfite, Sodium Salt Sodium Chlorate Sodium Chromate Sodium Chromate Sodium Cyanide... 

Official statements at the time, and to an extent even now, refer to only the less-toxic defoliants. However, Assistant Secretary of Defence, Cyrus Vance, when asked in 1965 whether arsenic and cyanide compounds were being sprayed over South Vietnam, replied, We are making limited use of them in the southern part of Vietnam but not yet in the north. 52 It is hard to escape the conclusion then that aerial spraying of cacodylic acid continued unabated to at least 1971 and caused unknown casualties to human and animal life below. 

Shock-sensitive, detonable compounds (such as sodium azide, dry picric acid) or extremely poisonous materials (such as cyanides, osmium tetroxide, cacodylic acid, tetrodotoxin, picrotoxin, ricin) should be stored in locked cabinets. DEA-regulated substances (e.g., pentobarbital, phenobarbital)... 

In 10 mM acetate buffer at pH 5.5 and with 4 /tM EDTA present to reduce the catal5dic effects of iron salts, the order of inhibition was determined to be CN- > Ng- > F- > I- > NO3- > Cl- > Br- > OCN" > SCN- > SeCN- > (CIO4-, tetraborate, boric acid, phosphate, sulfate and cacodylate). Clearly the strongest inhibitors are those with metal binding capabilities although this features alone does not readily correlate the series. Indeed, there are complexities which are apparent imder detailed scrutiny and which suggest a very compUcated pattern of inhibitory action by these anions. Curzon and his co-workers and other investigators have carried out detailed studies of the inhibition by azide, cyanide, the halides, and mixtures of various anionic inhibitors. 

Silver cyanide Silver potassium cyanide silvicide Cacodylic acid silylated enol ether mfg. 

Later analyses showed that the substance had this formula, and Bunsen adopted the proposal of Berzelius that it should be named Kakodyloxyd (cacodyl oxide), from KaKa>8rj9y stinking, and regarded as the oxide of a radical cacodyl C4Hi2As2 = Kd (Berzelius, with reasons, used Kk). By the action of concentrated acids on cacodyl oxide, Bunsen prepared the chloride, iodide, and fluoride of cacodyl, and the cyanide, diese schone aber beispiellos giftige Verbindung by the same method, but more conveniently by distilling cacodyl oxide and mercuric cyanide. He also prepared cacodyl sulphide and selenide. 

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