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|Section2= |Section7= }} 2-Nitrobenzaldehyde is an organic aromatic compound containing a nitro group ortho to formyl. 2-Nitrobenzaldehyde once was produced as an intermediate in the synthesis of the popular dye Indigo. ==Synthesis== The main routes to nitrobenzaldehyde begin with the nitration of styrene and cinnamic acid followed by the conversions of the resulting 2-nitrostyrene and 2-nitrocinnamic acids. Cinnamaldehyde can also be nitrated, e.g. in a solution of acetic anhydride in acetic acid, in high-yield to 2-nitrocinnamaldehyde.〔(o-NITROCINNAMALDEHYDE, nitration of cinnamaldehyde, organic-synthesis )〕 This compound is then oxidized to 2-nitrocinnamic acid, which is decarboxylated to the 2-nitrostyrene. The vinyl group can be oxidized in a number of different ways to yield 2-nitrobenzaldehyde.〔(Selective aerobic oxidation of styrene to benzaldehyde catalyzed by water-soluble palladium(II) complex in water ), Bo Feng, Zhenshan Hou, Xiangrui Wang, Yu Hu, Huan Li and Yunxiang Qiao〕 In one synthetic process, toluene is mono-nitrated at cold temperatures to 2-nitrotoluene, with about 58% being converted to the ortho- isomer, the remaining forming meta- and para- isomers.〔http://www.thecatalyst.org/experiments/AndersonS/AndersonS.html Product Distribution in the Nitration of Toluene, Steven W. Anderson, January 7, 1999〕 The 2-nitrotoluene can then be oxidized to yield 2-nitrobenzaldehyde.〔(Synthesis of 2-Nitrobenzaldehyde from 2-Nitrotoluene ), Alexander Popkov〕 Alternatively, 2-nitrotoluene as formed above can be halogenated to a 2-nitrobenzyl halide followed by oxidation with DMSO and sodium bicarbonate to yield 2-nitrobenzaldehyde, which is subsequently purified with the creation of a bisulfite adduct.〔(【引用サイトリンク】url=http://www.google.com/patents?hl=en&lr=&vid=USPAT4297519&id=uOwBAAAAEBAJ&oi=fnd&dq=2-nitrobenzyl+bromide&printsec=abstract#v=onepage&q=2-nitrobenzyl%20bromide&f=false )〕 The nitration of benzaldehyde produces mostly 3-nitrobenzaldehyde, with yields being about 19% for the ortho-, 72% for the meta- and 9% for the para isomer.〔(Structure of Benzene, California State University Dominguez Hills )〕 For this reason, the nitration of benzaldehyde to yield 2-nitrobenzaldehyde is not cost-effective. 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「2-Nitrobenzaldehyde」の詳細全文を読む スポンサード リンク
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