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Organobismuth chemistry is the chemistry of organometallic compounds containing a carbon to bismuth chemical bond. According to one reviewer, applications are rare even though bismuth and bismuth compounds are the least toxic among the heavy metals and are relatively cheap.〔"Bismuth-Mediated Organic Reactions", Ollevier, T. Ed., Topics in Current Chemistry, 2012, Springer Verlag, Berlin, vol. 311, 277 p. http://www.springer.com/chemistry/organic+chemistry/book/978-3-642-27238-7, ''Bismuth Reagents and Catalysts in Organic Synthesis'' Axel Jacobi von Wangelin in ''Transition Metals for Organic Synthesis Building Blocks and Fine Chemicals'' Beller, Matthias / Bolm, Carsten (eds.)〕 The main bismuth oxidation states are Bi(III) and Bi(V) as in all higher group 15 elements. The energy of a bond to carbon in this group decreases in the order P > As > Sb > Bi.〔C. Elschenbroich, A. Salzer ''Organometallics : A Concise Introduction'' (2nd Ed) (1992) from Wiley-VCH: Weinheim. ISBN 3-527-28165-7〕 The first reported use of bismuth in organic chemistry was in oxidation of alcohols by Challenger in 1934 (using Ph3Bi(OH)2).〔''Organo-derivatives of bismuth and thallium'' Frederick Challenger and Oswald V. Richards, J. Chem. Soc., 1934, 405 〕 Knowledge about methylated species of bismuth in environmental and biological media is very limited. ==Organobismuth(V) chemistry== Bi(V) compounds are strongly oxidizing due to the inert pair effect and relativistic effects. Oxidizing agents are Ph3Bi(OOtBu)2, Ph3BiCO3 and (Ph3BiCl)2O. Substrates for oxidation are oximes, thiols, phenols and phosphines.〔''Organobismuth Chemistry'' Hitomi Suzuki, Yoshihiro Matano Elsevier, 2001〕 Compounds such as Ph5Bi and Ph3BiCl2 have been used in the arylation of arene compounds and 1,3-dicarbonyl compounds:〔''Bismuth(V) reagents in organic synthesis'' Derek H.R. Barton and Jean-Pierre Finet Pure & Appl. Chem., Vol. 59, No. 8, pp. 937—946, 1987.〕 :Pentaphenylbismuth arylation Bi(V) compounds can be accessed through Bi(III) compounds for example: :Me3Bi + SOCl2 → Me3BiCl2 :Me3BiCl2 + 2 MeLi → Me5Bi Bi(V) easily forms an onium ion for example: :Ph5Bi + BPh3 → Ph4Bi+()− or an ate complex for example: :Ph5Bi + PhLi → Li+() The thermal stability of R5M compounds decrease in the order As > Sb > Bi and aryl compounds are more stable than alkyl compounds. Me5Bi decomposes explosively at 20 °C. 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「Organobismuth chemistry」の詳細全文を読む スポンサード リンク
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