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Isothiocyanate is the chemical group –N=C=S, formed by substituting the oxygen in the isocyanate group with a sulfur. Many natural isothiocyanates from plants are produced by enzymatic conversion of metabolites called glucosinolates. These natural isothiocyanates, such as allyl isothiocyanate, are also known as mustard oils. An artificial isothiocyanate, phenyl isothiocyanate, is used for amino acid sequencing in the Edman degradation. ==Synthesis and reactions== The general method for the formation of isothiocyanates proceeds through the reaction between a primary amine (e.g. aniline) and carbon disulfide in aqueous ammonia. This results in precipitation of the ammonium dithiocarbamate salt, which is then treated with lead nitrate to yield the corresponding isothiocyanate. Another method relies on a tosyl chloride mediated decomposition of dithiocarbamate salts that are generated in the first step above. : Isothiocyanates may also be accessed via the thermally-induced fragmentation reactions of 1,4,2-oxathiazoles. This synthetic methodology has been applied to a polymer-supported synthesis of isothiocyanates. Isothiocyanates are weak electrophiles. Akin to the reactions of carbon dioxide, nucleophiles attack at carbon. Reflecting their electrophilic character, isothiocyanates are susceptible to hydrolysis. 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「Isothiocyanate」の詳細全文を読む スポンサード リンク
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