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Organogold chemistry is the study of compounds containing carbon-gold bonds. They are studied in academic research, but have not received widespread use otherwise. The dominant oxidation states for organogold compounds are I with coordination number 2 and a linear molecular geometry and III with CN = 2 and a planar molecular geometry.〔Elschenbroich, C. and Salzer, A. (1992) ''Organometallics : A Concise Introduction''. Wiley-VCH: Weinheim. ISBN 3-527-28165-7〕 The gold carbide Au2C2 was discovered in 1900. ==Gold(I)== Gold(I) complexes are 2-coordinate, linear, diamagnetic, 14 electron species. They exist as adducts LAuR with as ligand L for instance a triphenylphosphine or an isocyanide. The ligand prevents reduction of Au(I) to metallic Au(0) with dimerization of the organic residue. Gold(I) can also exist as the aurate MAuR2 (the ate complex) whereby the cation is usually fitted with a complexing agent to improve stability. The AuR2− anion is also linear just as other M(d10) species such as Hg(Me)2 and Pd(Me)22+. Gold is known to form acetylides (capable of forming polymeric structures), carbenes and carbynes. The classic method for the preparation of LAuR compounds is by reaction of a Grignard reagent with a gold(I) halide. A subsequent reaction with an organolithium R-Li forms the ate complex. In a special group of compounds, an aryl carbon atom acts as a bridge between two gold atoms. One such compound, (MesAu)5,is formed in a reaction between Au(CO)Cl and the mesityl Grignard. Carbon can be coordinated with gold up to a value to 6. Compounds of the type C(AuL)4 are isolobal with methane and those of type C(AuL)5+ isolobal with the methanium ion. :Organogold compounds Gold cyanide compounds (MAu(CN)2) are of some importance to gold cyanidation, a process for the extraction of gold from low-grade ore. The carbon to metal bond in metal cyanides is usually ionic but evidence exists that the C-Au bonding in the gold cyanide ion is covalent. 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「Organogold chemistry」の詳細全文を読む スポンサード リンク
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