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Organochromium chemistry is a branch of organometallic chemistry that deals with organic compounds containing a chromium to carbon bond and their reactions.〔Review: ''Carbon-Carbon Bond Formations Involving Organochromium(III) Reagents'' Furstner, A. Chem. Rev.; (Review); 1999; 99(4); 991-1046. 〕〔Review: ''From Hein to Hexene: Recent Advances in the Chemistry of Organochromium -Complexes'' Jolly, P. W. Acc. Chem. Res.; (Article); 1996; 29(11); 544-551. 〕 The field is of some relevance to organic synthesis. The relevant oxidation states for chromium range from -2 to +6. ==History== The first organochromium compound was described in 1919 by Franz Hein.〔''Notiz über Chromorganoverbindungen'' (p 195-196) F. Hein Berichte der deutschen chemischen Gesellschaft (A and B Series) Volume 52, Issue 1 , Pages 195 - 196 1919 〕 He treated phenylmagnesium bromide with chromium(III) chloride to give a new product (after hydrolysis) which he incorrectly identified as pentaphenyl chromium bromide (Ph5CrBr). Years later, in 1957 H.H. Zeiss et al. repeated Hein's experiments and correctly arrived at a cationic bisarene chromium sandwich compound (Ar2Cr+).〔''π-Complexes of the Transition Metals. I. Hein's Polyaromatic Chromium Compounds'' Harold H. Zeiss, Minoru Tsutsui J. Am. Chem. Soc.; 1957; 79(12); 3062-3066. 〕 Bis(benzene)chromium itself was discovered around the same time in 1956 by Ernst Otto Fischer by reaction of chromium(III) chloride, benzene and aluminum chloride.〔''Zur Frage der Struktur der Chrom-phenyl-Verbindungen. Über Aromatenkomplexe von Metallen VI'' (p 1809-1815) E. Otto Fischer, Dietlinde Seus Chemische Berichte Volume 89, Issue 8 , Pages 1809 - 1815 1956 〕〔''Zur Frage der Struktur der Chrom-phenyl-Verbindungen. Bemerkungen zur Abhandlung von E. O. Fischer und D. Seus'' (p 1816-1821) Fr. Hein Chemische Berichte Volume 89, Issue 8 , Pages 1816 - 1821 1956 〕 The related compound chromocene was discovered a few years earlier in 1953 also by Fischer.〔Fischer, E. O.; Hafner, W. Z. Naturforsch. 1953, 8b, 444.〕 In another development, Anet and Leblanc also in 1957 prepared a benzyl chromium solution from benzyl bromide and chromium(II) perchlorate.〔F. A. L. Anet, E. Leblanc "A Novel Organochromium Compound" J. Am. Chem. Soc.; 1957; 79(10), 2649-2650. 〕 This reaction involves one-electron oxidative addition of the carbon-bromine bond, a process which was shown by Kochi〔''Reduction of Organic Halides by Chromium(II). Mechanism of the Formation of Benzylchromium Ion'' Jay K. Kochi, Dennis D. Davis J. Am. Chem. Soc.; 1964; 86(23); 5264-5271. 〕〔''Stereochemistry of reductive elimination by chromium(II) complexes '' Jay K. Kochi, David M. Singleton J. Am. Chem. Soc.; 1968; 90(6); 1582-1589. 〕 to be a case of double single electron transfer, first to give the benzyl free radical and then to the benzyl anion. : G. Wilke et al. introduced tris-(η-allyl)chromium in 1963 as an early Ziegler-Natta catalyst (but not successful in the long run)〔Wilke, G. ''Cyclooligomerisation von Butadien und Übergangsmetall--Komplexe'' Angewandte Chemie, 1963 Volume 75, pp. 10-20. 〕 Chromocene compounds were first employed in ethylene polymerization in 1972 by Union Carbide〔Frederick J. Karol, George L. Karapinka, Chisung Wu, Alan W. Dow, Robert N. Johnson, Wayne L. Carrick ''Chromocene catalysts for ethylene polymerization: Scope of the polymerization'' Journal of Polymer Science Part A-1: Polymer Chemistry 1972 Volume 10, Issue 9, pp. 2621-2637. 〕 and continue to used today in the industrial production of high-density polyethylene. The organochromium compound (phenylmethoxycarbene)pentacarbonylchromium, Ph(OCH3)C=Cr(CO)5 was the first carbene complex to be crystallographically characterized by Fischer in 1967 (now called a Fischer carbene).〔Ernst Otto Fischer, Alfred Maasböl ''Übergangsmetall-Carben-Komplexe, II. Phenylmethoxycarben- und Methylmethoxycarben-pentacarbonyl-chrom, -molybdän, -wolfram und -cyclopentadienyl-dicarbonyl-mangan'' Chemische Berichte 1967 Volume 100, pp. 2445-2456 〕 The first ever carbyne, this one also containing chromium, made its debut in 1973.〔Ernst Otto Fischer, Gerhard Kreis, Cornelius G. Kreiter, Jörn Mülle, Gottfried Huttner, Hans Lorenz ''trans-Halogeno-alkyl(aryl)carbin-tetracarbonyl-Komplexe von Chrom, Molybdän und Wolfram-Ein neuer Verbindungstyp mit Übergangsmetall-Kohlenstoff-Dreifachbindung'' Angewandte Chemie 1973, Volume 85, Issue 14, p 618-620. 〕 : The first example of a proposed metal-metal quintuple bond is found in a compound of the type ()2, where Ar is a bulky aryl ligand. 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「Organochromium chemistry」の詳細全文を読む スポンサード リンク
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