fatty aldehyde
Occurrence
Fatty aldehydes are a natural component of many natural ingredients such as the essential oils of various citrus fruits. Decanal, for example, is a component of orange peel.Kehai Liu, Qiulin Chen, Yanjun Liu, Xiaoyan Zhou, Xichang Wang: "Isolation and Biological Activities of Decanal, Linalool, Valencene, and Octanal from Sweet Orange Oil". In: Journal of Food Science 77, 2012, S. C1156–C1161, doi:10.1111/j.1750-3841.2012.02924.x. The pheromone cocktails of various insect pheromones contain fatty aldehydes.Gerhard Kasang, Karl Ernst Kaißling, Otto Vostrowsky, Hans Jürgen Bestmann: "Bombykal, eine zweite Pheromonkomponente des Seidenspinners Bombyx mori L." In: Angewandte Chemie. 90, 1978, S. 74–75, doi:10.1002/ange.19780900132. Fat aldehydes were also detected in the heart muscle of mammals.John R. Gilbertson et al.: "Natural occurrence of free fatty aldehydes in bovine cardiac muscle". In: Journal of Lipid Research 13.4 (1972): S. 491–499.
Preparation
Fatty aldehydes can be prepared by dehydrogenation of fatty alcohols on copper-zinc catalysts.{{Cite patent|country=DE|number=10044809|title= Verfahren zur Herstellung von Aldehyden|pubdate=2002-01-10|invent1= Albrecht Schwerin, Lothar Friesenhagen, Gerrit Pelzer, Bernhard Gutsche}} By the hydroformylation of alkenes, fatty aldehydes are produced on a large industrial scale.Ernst Wiebus, Boy Cornils: "Die großtechnische Oxosynthese mit immobilisiertem Katalysator" In: Chemie Ingenieur Technik 66, 1994, S. 916–923, doi:10.1002/cite.330660704.
Use
A large proportion of the fatty aldehydes prepared by hydroformylation is directly processed further to fatty alcohols. Many fatty aldehydes find use as a fragrance in perfume production. An example is 2-methylundecanal which is the typical odor component of Chanel No. 5.{{cite web|title=Chemistry in its element - 2-Methylundecanal|url=http://www.rsc.org/chemistryworld/podcast/CIIEcompounds/transcripts/2-methylundecanal.asp|url-status=dead|accessdate=2014-06-20|archiveurl=https://web.archive.org/web/20140528084048/http://www.rsc.org/chemistryworld/podcast/CIIEcompounds/transcripts/2-methylundecanal.asp|archivedate=2014-05-28|language=German}} Decanal, whose sweet, flowery odor reminiscents of orange peels, is used, among other things, as a flavoring agent in the food industry and as a perfume in the perfume industry.