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|Section2= |Section4= |Section7= |Section8= }} Benzaldehyde (C6H5CHO) is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. This colorless liquid has a characteristic pleasant almond-like odor. In fact, benzaldehyde is the primary component of bitter almond oil and can be extracted from a number of other natural sources.〔http://www.freepatentsonline.com/1416128.pdf, United States Patent 1416128 - Process of treating nut kernels to produce food ingredients.〕 Benzaldehyde was first extracted from bitter almonds in 1803 by the French pharmacist Martrès.〔In 1803 C. Martrès published a manuscript on the oil of bitter almonds: "Recherches sur la nature et le siège de l'amertume et de l'odeur des amandes amères" (Research on the nature and location of the bitterness and the smell of bitter almonds). However, the memoir was largely ignored until an extract was published in 1819: Martrès ''fils'' (1819) ("Sur les amandes amères," ) ''Journal de Pharmacie'', vol. 5, pages 289-296.〕 In 1832 German chemists Friedrich Wöhler and Justus von Liebig first synthesized benzaldehyde.〔Wöhler and Liebig (1832) ("Untersuchungen über das Radikal der Benzoesäure" ) (Investigations of the radical of benzoic acid), ''Annalen der Pharmacie'', vol. 3, pages 249-282.〕 == Production == Benzaldehyde can be obtained by many processes. In the 1980s, an estimated 18 million kilograms were produced annually in Japan, Europe, and North America, a level that can be assumed to continue. Currently liquid phase chlorination and oxidation of toluene are the main routes. Numerous other methods have been developed, such as the partial oxidation of benzyl alcohol, alkali hydrolysis of benzal chloride, and the carbonylation of benzene.〔Friedrich Brühne and Elaine Wright “Benzaldehyde” in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. 〕 Benzaldehyde can be synthesized from cinnamaldehyde obtained from the oil of cinnamon by refluxing in aqueous/alcoholic solution between 90 °C and 150 °C with a base (most commonly sodium carbonate or bicarbonate) for 5 to 80 hours,〔http://www.patentstorm.us/patents/pdfs/patent_id/4617419.html, Process for preparing natural benzaldehyde and acetaldehyde, natural benzaldehyde and acetaldehyde compositions, products produced thereby and organoleptic utilities therefor, Charles Wienes, Middletown; Alan O. Pittet, Atlantic Highlands, both of N.J.〕 followed by distillation of the formed benzaldehyde. This reaction also yields acetaldehyde. 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「Benzaldehyde」の詳細全文を読む スポンサード リンク
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