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|Section2= |Section7= |Section8= }} Sodium borohydride, also known as sodium tetrahydridoborate, and sodium tetrahydroborate is an inorganic compound with the formula NaBH4. This white solid, usually encountered as a powder, is a versatile reducing agent that finds wide application in chemistry, both in the laboratory and on a technical scale. Large amounts are used for bleaching wood pulp.〔〔Istek, A. and Gonteki, E. "Utilization of sodium borohydride (NaBH4) in kraft pulping process." Retrieved online on 25 September 2014 at http://www.jeb.co.in/journal_issues/200911_nov09/paper_05.pdf.〕 The compound is soluble in alcohols and certain ethers but reacts with water in the absence of a base.〔Banfi, L.; Narisano, E.; Riva, R.; Stiasni, N.; Hiersemann, M. "Sodium Borohydride" in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. .〕 The compound was discovered in the 1940s by H. I. Schlesinger, who led a team that developed metal borohydrides for wartime applications (in particular, looking for a uranium compound more volatile than the hexafluoride to be used in isotope separation by gaseous diffusion; this line of research did not yield useful results). Their work was declassified and published only in 1953. ==Properties== Sodium borohydride is an odorless white to gray-white microcrystalline powder which often forms lumps. It can be purified by recrystallization from warm (50 °C) diglyme.〔Brown, H. C. “Organic Syntheses via Boranes” John Wiley & Sons, Inc. New York: 1975. ISBN 0-471-11280-1. page 260-1.〕 Sodium borohydride is soluble in protic solvents such as water and lower alcohols; it will also react with these solvents to produce H2; however, these reactions are fairly slow. Complete decomposition in excess methanol can take nearly 90 min at 20 °C. It will decompose in neutral or acidic aqueous solutions but is stable at pH 14.〔 These conditions can be exploited to allow sodium borohydride to react in a homogeneous manner, with reduced lifespan being traded against increased reactivity. 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「Sodium borohydride」の詳細全文を読む スポンサード リンク
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