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|Section2= |Section3= |Section7= |Section8= }} Di-''tert''-butyl dicarbonate is a reagent widely used in organic synthesis.〔M. Wakselman, "Di-''t''-butyl Dicarbonate" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. .〕 This carbonate ester reacts with amines to give ''N''-''tert''-butoxycarbonyl or so-called Boc derivatives. These derivatives do not behave as amines, which allows certain subsequent transformations to occur that would have otherwise affected the amine functional group. The Boc can later be removed from the amine using acids. Thus, Boc serves as a protective group, for instance in solid phase peptide synthesis. It is unreactive to most bases and nucleophiles, allowing for an orthogonal Fluorenylmethyloxycarbonyl chloride (FMOC-Cl) protection. ==Preparation== Di-''tert''-butyl dicarbonate is inexpensive, so it is usually purchased. Classically, this compound is prepared from ''tert''-butanol, carbon dioxide, phosgene, using DABCO as a base: : This route is currently employed commercially by manufacturers in China and India. European and Japanese companies use the reaction of sodium tert-butylate with carbon dioxide, catalysed by ''p''-toluenesulfonic acid or methanesulfonic acid. This process involves a distillation of the crude material yielding a very pure grade. Boc anhydride is also available as a 70% solution in toluene or THF. As boc anhydride may melt at ambient temperatures, its storage and handling is sometimes simplified by using a solution. 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「Di-tert-butyl dicarbonate」の詳細全文を読む スポンサード リンク
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