Английская Википедия:Isovaleraldehyde
Isovaleraldehyde organic compound, also known as 3-methylbutanal, with the formula (CH3)2CHCH2CHO. It is an aldehyde, a colorless liquid at STP,[1] and found in low concentrations in many types of food.[2] Commercially it is used as a reagent for the production of pharmaceuticals, perfumes and pesticides.[3]
Synthesis
Synthetic routes for the production of isovaleraldehyde vary. One method is by the hydroformylation of isobutene:
A small amount of 2,2-dimethylpropanal (Шаблон:Chem2 side product is also generated.[3]
Another method of production involves the isomerization of 3-methylbut-3-en-1-ol using CuO–ZnO as a catalyst. A mixture of 3-methylbut-3-en-1-ol and 3-methylbut-2-en-1-ol may also be used. These starting materials are obtained from a reaction between isobutene and formaldehyde:[3]
- CH3CH3CCH2 + CH2O → (CH3)2CHCH2CHO
Finally, in beer the compound is produced via a reaction between the amino acid leucine and reductones in the malt.[4]
Occurrences and uses
As it can be derived from leucine, the occurrence of isovaleraldehyde is not limited to beer. The compound has found to be a flavor component in many different types of foods. It is described as having a malty flavor and has been found in cheese, coffee, chicken, fish, chocolate, olive oil, and tea.[2][5]
The compound is used as a reactant in the synthesis of a number of compounds. Notably it is used to synthesize 2,3-dimethylbut-2-ene, and is then converted to 2,3-dimethylbutane-2,3-diol and methyl tert-butyl ketone, better known as pinacolone. Pinacolone itself is then used in synthesis for number of pesticides. Additionally, a range of pharmaceuticals, such as butizide, are synthesized from isovaleraldehyde and its corresponding acid.[3] It is a common reagent or building block in organic synthesis.[6][7]
Acid-catalyzed cyclic trimerization of Isovaleraldehyde gives 2,4,6-Triisobutyl-1,3,5-trioxane [68165-40-2]. This is a flavouring agent that can be used in confectionary, tobacco, and other foodstuffs, toothpastes and the like.[8] It is described as imparting a creamy, dairy, vanilla chocolate and berry flavour.
According to IFF, isovaleraldehyde is used as a food flavorant additive.[9]
References
- ↑ Шаблон:Cite book
- ↑ 2,0 2,1 Шаблон:Cite encyclopedia
- ↑ 3,0 3,1 3,2 3,3 Шаблон:Ullmann
- ↑ Шаблон:Cite encyclopedia
- ↑ Шаблон:Cite encyclopedia
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite journal
- ↑ Donald Arthur Withycombe, et al. Шаблон:US patent, Шаблон:US patent (1978 to International Flavors and Fragrances Inc).
- ↑ http://lmrnaturals.iff.com/en/site-services/flavor-online-compendium-iframe#3-methylbutyraldehyde
