Violet leaf aldehyde

In addition to the straight-chain saturated aldehydes, a number of branched-chain and unsaturated aliphatic aldehydes are important as fragrance and flavoring materials. The double unsaturated 2-trcucumber aroma), is one of the most potent fragrance and flavoring substances it is, therefore, only used in very small amounts. 2-frfatty odor character is indispensible in chicken meat flavor compositions. 

The absolute is a dark green to brown liquid with a strong, green odor. The main constituent of the volatile fraction is 2-trani-6-cw-nonadienal [557-48-2] (violet leaf aldehyde) [818, 819]. 

SYNS CUCUMBER ALDEHYDE FEMA No. 3317 2,6-NONADIENAL trans,cis-2,6-NONADIENAL trans-2,ds-6-NONADIENAL VIOLET LEAF ALDEHYDE... 

E,Z)-2,6-N. (violet leaf aldehyde) bp. 88 °C (1.3 kPa), LD50 (rat p.o.) >5 g/kg fatty-green odor of violet leaves in which it was first detected in 1925, ( ,Z)-structure assigned in 1944. It also occurs in vegetable flavors ( impact compound in cucumber), fruit flavors (guava, melon, mango), meat, and seafood flavors. For synthesis, see Lit.. ... 

CHC Powerful green cucumber, melon, violet leaf aldehydic with a fresh vegetable note... 

In Coriandre (Couturier 1973) the top note is of coriander, ylang, styrallyl acetate, and undecylenic aldehyde, with geranium as part of the rose note. The type of rose base, which probably makes up some 10% of the formula, is a classic combination of phenylethyl alcohol, citronellol, geraniol, geranyl acetate, honey notes such as ethyl phenylacetate and phenylethyl phenylacetate, phenylacetaldehyde, rosatol, camomile, and violet leaf. Apart from hydroxycitronellal, Lyral, and phenylacetaldehyde glyceroacetal add to the muguet character. 

The enzymic formation of aldehydes, ketones, alcohols, and oxoacids (from linoleic and linolenic acids) on disruption of plant tissues is an important biosynthetic pathway by which fruit and vegetable volatiles are formed. Some examples are (E)-2-hexenal ("leaf aldehyde") and ( )-3-hexenol ("leaf alcohol") in tea (E)-2-hexenal in apples (E,Z)-2,6-nonadienal ("violet Teaf aldehyde") and (E)-2-nonenal in cucumber ( Z)-5-nonenal in musk melon (Z,Z) -3,6-nonadienol in water melon, and 1-octen-3-ol ("mushroom alcohol") in certain edible mushrooms and Fungi. The enzyme system is highly substrate specific to a (Z,Z)-1,4-pentadiene system (like lipoxygenase) splitting the >C = C< double bond at the W - 6 and/or W - 9 position. Therefore linoleic-, linolenic-, and arachidonic acids are natural substrates. It seems to be a common principle in leaves, fruits, vegetables, and basidiomycetes. 

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