Natural occurrence and uses of 3-hepten-2-one

3-Hepten-2-one is a colorless oily liquid with a powerful green-grassy, pungent odor. It is insoluble in water, but soluble in alcohol and oils. The nature occurrence of 3-hepten-2-one was reported found in hop oil, roasted filbert (Corylus avellano), and muruci (Brysonima crassigolia). It was also reported that 3-hepten-2-one is included in volatile compounds derived from cephalic glands of the fire bee Trigona (Oxytrigona) tataira by GC-MS. This compound can be synthesized by reacting 1-pentyne with acetic anhydride to yield 3-heptyn-2-one, which is consequently converted to cis-3-hepten-2-one by partial catalytic hydrogenation. The trans-form is probably obtained from trans-2-hexenic acid treated with methyl lithium. 

Typically, 3-Penten-2-one and 3-hepten-2-one were found in mouse urine together with short- and medium-chain aliphatic aldehydes, while 3-penten-2-one is a biomarker for increased acetaldehyde in mouse urine. However, their origin and clinical significance are unknown. Further studies of comparative analysis of volatile constituents from mice body and their urine showed that 3-hepten-2-one is one of the components only found in urine volatiles but not in body scent of male C57BL/6J mice, while a total of 67 components were observed only in the volatiles from the body of mice. Therefore, when analyze volatile compounds in mouse urine, 3-hepten-2-one is selected as a characteristic compound to analyze. In a study of analyzing some active principles of herb plants by GC/MS, 3-hepten-2-one was used as external standard to mix with other components to form a standard mixture for recovery determination. Another study also employed 3-hepten-2-one as an external standard to determine the absolute recovery values by using external calibration with the standard 3-hepten-2-one, as it is known to be usually present in some herbs. Volatile fraction composition, including 3-hepten-2-one, and physicochemical parameters were analyzed as tools for the differentiation of lemon blossom honey and orange blossom honey. 

In addition, 3-hepten-2-one was also used in the process of organocatalytic enantioselective aza-Michael addition of purine bases to α, β-unsaturated ketones. Several bifunctional catalysts were screened to evaluate their ability to promote the aza-Michael addition of 6-chloro-9H-purine to 3-hepten-2-one at room temperature in toluene in the presence of benzoic acid as cocatalyst. The utility of this method was also applied for the synthesis of enantioenriched non-natural nucleoside analogues with potential biological activities.

Another important use of 3-hepten-2-one is to be added as a flavoring ingredient in foods for caraway, passion fruit and pineapple flavors. It is also used for the fragrance concentrate (0.5000%). 

References

Burdock GA. Encyclopedia of food & color additives. CRC Press; 2014 Jul 29.

Bian, Z., Fales, H.M., Blum, M.S., Jones, T.H., Rinderer, T.E. and Howard, D.F., 1984. Chemistry of cephalic secretion of fire beeTrigona (Oxytrigona) tataira. Journal of chemical ecology, 10(3), pp.451-461.

https://spectrabase.com/spectrum/231ltWuFdEG

Walker, V., Mills, G.A. and Stansbridge, E.M., 2009. 3-Penten-2-one, a novel aldehyde adduct, is a biomarker for increased acetaldehyde in urine. Journal of Chromatography B, 877(8-9), pp.784-790.

Röck, F., Mueller, S., Weimar, U., Rammensee, H.G. and Overath, P., 2006. Comparative analysis of volatile constituents from mice and their urine. Journal of chemical ecology, 32(6), pp.1333-1346.