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|Section2= |Section5= |Section7= |Section8= }} Tabun or GA is an extremely toxic chemical substance. It is a clear, colorless, and tasteless liquid with a faint fruity odor.〔(Facts About Tabun ), National Terror Alert Response System〕 It is classified as a nerve agent because it fatally interferes with normal functioning of the mammalian nervous system. Its production is strictly controlled and stockpiling outlawed by the Chemical Weapons Convention of 1993. Tabun is the first of the ''G-series'' nerve agents along with GB (sarin), GD (soman) and GF (cyclosarin). Although pure tabun is clear, less-pure tabun may be brown. It is a volatile chemical, although less so than either sarin or soman.〔 Tabun can be destroyed with bleaching powder, though the poisonous gas cyanogen chloride is produced. ==Synthesis== Tabun was made on an industrial scale by Germany during World War II, based on a process developed by Gerhard Schrader. In the chemical agent factory in Dyhernfurth an der Oder, codenamed "Hochwerk", at least 12,000 metric tons of this agent were manufactured between 1942 and 1945. The manufacturing process consisted of two steps, the first being reaction of gaseous dimethylamine (1) with an excess of phosphoryl chloride (2), yielding dimethylamidophosphoric dichloride (3, codenamed "Produkt 39" or "D 4") and dimethylammonium chloride (4). The dimethylamidophosphoric dichloride thus obtained was purified by vacuum distillation and thereafter transferred to the main Tabun production line. Here it was reacted with an excess of sodium cyanide (5), dispersed in dry chlorobenzene, yielding the intermediate dimethylamidophosphoric dicyanide (not depicted in the scheme) and sodium chloride (8); then, absolute ethanol (6) was added, reacting with the dimethylamidophosphoric dicyanide to yield tabun (7) and hydrogen cyanide (9). After the reaction, the mixture (consisting of about 75% chlorobenzene and 25% tabun, along with insoluble salts and the rest of the hydrogen cyanide) was filtered to remove the insoluble salts and vacuum-distilled to remove hydrogen cyanide and excess chlorobenzene, so yielding the technical product, consisting either of 95% tabun with 5% chlorobenzene (Tabun A) or (later in the war) of 80% tabun with 20% chlorobenzene (Tabun B).〔Lohs, KH: Synthetische Gifte. 3., überarb. u. erg. Aufl., 1967, Deutscher Militärverlag, Berlin (East).〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tabun (nerve agent)」の詳細全文を読む スポンサード リンク
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