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|Section2= |Section9= }} Diazene, also called diimine or diimide, is a compound having the formula (NH)2. It exists as two geometric isomers, E and Z. Diazene is also the parent member of the entire class of azo compounds with the formula (NR)2, where R is an organyl group. Thus, azobenzene is an example of an organic diazene. ==Synthesis== The traditional route to diazene involves oxidation of hydrazine with hydrogen peroxide or air. Alternatively the decarboxylation of azodicarboxylic acid affords diazene: :(NCO2H)2 → (NH)2 + 2 CO2 Diazene can also be efficiently generated by elimination of sulfonohydrazides using a suitable base. For example, 2,4,6-triisopropylbenzenesulfonohydrazide eliminates diazene upon treatment with sodium bicarbonate, a very mild base. Because of its instability, diazene is generated and used ''in-situ''. A mixture of both the ''cis'' (''Z-'') and ''trans'' (''E-'') isomers is produced. Both isomers are unstable, and they undergo a slow interconversion. The ''trans'' isomer is more stable, but the ''cis'' isomer is the one that reacts with unsaturated substrates, therefore the equilibrium between them shifts towards the ''cis'' isomer due to Le Chatelier's principle. Some procedures call for the addition of carboxylic acids, which catalyse the cis–trans isomerization.〔 Diazene decomposes readily. Even at low temperatures, the more stable ''trans'' isomer rapidly undergoes various disproportionation reactions, primarily forming hydrazine and nitrogen gas: :2 HN=NH → H2N–NH2 + N2 Because of this competing decomposition reaction, reductions with diazene typically require a large excess of the precursor reagent. 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「Diazene」の詳細全文を読む スポンサード リンク
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