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An oxime is a chemical compound belonging to the imines, with the general formula R1R2C=N O H, where R1 is an organic side-chain and R2 may be hydrogen, forming an aldoxime, or another organic group, forming a ketoxime. O-substituted oximes form a closely related family of compounds. Amidoximes are oximes of amides with general structure RC(=NOH)(NRR'). Oximes are usually generated by the reaction of hydroxylamine and aldehydes or ketones. The term oxime dates back to the 19th century, a portmanteau of the words ''oxygen'' and ''imine''.〔The name "oxime" is derived from "oximide" (i.e., oxy- + amide). According to the German organic chemist Victor Meyer (1848–1897) – who, with Alois Janny, synthesized the first oximes – an "oximide" was an organic compound containing the group (=N-OH) attached to a carbon atom. The existence of oximides was questioned at the time (ca. 1882). (See page 1164 of: Victor Meyer und Alois Janny (1882a) ("Ueber stickstoffhaltige Acetonderivate" ) (On nitrogenous derivatives of acetone), ''Berichte der Deutschen chemischen Gesellschaft'', 15: 1164–1167.) However, in 1882, Meyer and Janny succeeded in synthesizing methylglyoxime (CH3C(=NOH)CH(=NOH)), which they named "Acetoximsäure" (acetoximic acid) (Meyer & Janny, 1882a, p. 1166). Subsequently, they synthesized 2-propanone, oxime ((CH3)2C=NOH), which they named "Acetoxim" (acetoxime), in analogy with Acetoximsäure. From Victor Meyer and Alois Janny (1882b) ("Ueber die Einwirkung von Hydroxylamin auf Aceton" ) (On the effect of hydroxylamine on acetone), ''Berichte der Deutschen chemischen Gesellschaft'', 15: 1324–1326, page 1324: "Die Substanz, welche wir, wegen ihrer nahen Beziehungen zur Acetoximsäure, und da sie keine sauren Eigenschaften besitzt, vorläufig Acetoxim nennen wollen, …" (The substance, which we – on account of its close relations to acetoximic acid, and since it possesses no acid properties – will, for the present, name "acetoxime," … )〕 ==Structure and properties== Oximes exist as two geometric stereoisomers: a ''syn'' isomer and an ''anti'' isomer. Aldoximes, except for aromatic aldoximes, which exist only as ''anti'' isomers, and ketoximes can be separated almost completely and obtained as a ''syn'' isomer and an ''anti'' isomer. Oximes have three characteristic bands in the infrared spectrum, at wavenumbers 3600 (O-H), 1665 (C=N) and 945 (N-O). In aqueous solution, aliphatic oximes are 102- to 103-fold more resistant to hydrolysis than analogous hydrazones. 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「oxime」の詳細全文を読む スポンサード リンク
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