6-methyl-3,8-nonadien

Also the rather inert nucleophile water reacted with piperylene yielding the telomer 6-methyl-3,8-nonadien-2-ol, only in low yields, however. 

See stmcture (107). This 4,5-position is saturated. 5-Isopropyl-8-methyl-6,8-nonadien-2-one. 5-Isopropyl-3-nonene-2,8-dione. 

Although the addition of hydrazine and its derivatives to acetylenic ketones has been studied in considerable detail, their interaction with hydrazones and mono-alkylhydrazones is less well known. Yandovskii and Klindukhova (74ZOR730) have studied the reaction between hydrazones and alkylhydrazones of aliphatic ketones with dipropynylketones and showed that hydrazones of acetone, methyl-ethylketone, and cyclohexane easily add to one of the triple bonds of dipropynylketone to form 4-methyl-1,1,3-trialkyl-2,3-diaza-l,4-nonadien-7-yn-6-ones (yields... 

Dioxo-6-methyl-2-(2-carboxy-athyl)- 722 Bicyclo[4.3.0]nonadien-(3,7)... 

Model systems indicate that aldehydes may also be produced by the action of polyphenoloxidases on amino acids in the presence of catechin, all of which are present in coffee beans at some stage between green and roasted. For example, valine yields isobutanal, leucine yields isopentanal, and isoleucine yields 2-methyl-butanal.14 Some of these aldehydes probably undergo condensation reactions in the acidic medium of the roasted bean when moisture is present.15 Some dienals in green coffee beans have recently been identified as (E,E)-2,4- and (E,Z)-2,4-nonadienal and (E,E)-2,4- and (E,Z)-2,4-decadienal.18... 

Hence, irradiation of l,l-diphenyl-8-methyl-l,7-nonadiene (5-la) in the presence of DCNB and Phen through an aqueous CuS04 filter solution (k > 334 nm) afforded octahydro-phenylanthracene 5-2a in 45% yield as the sole isomer (Scheme 5.1). In a similar way, 5-lb and 5-3 led to 5-2b and 5-4 in 57% and 71 % yields, respectively. 

The effects of the second double bond have also been examined. As might be expected from the case of styrene, the reaction of ( )-l, 3-decadiene and 2-( -hexy 1)-1,3-butadiene was very sluggish and did not proceed detectably over 12 h. Although 1,4-pentadiene itself has not yet been tested, ( )-5-methy1-1,4-undecadiene, ( )-4-( -butyI)-1,4-nonadienc, and (Z)-4-(trimethylsilyl)-l,4-nonadiene have provided the desired 2-methylated alcohols in 79, 84, and 69% yields, respectively [15]. Similarly, ( )-6-methyl-l,5-dodecadiene and ( )-5-(n-butyl)-... 

Crust volatiles were isolated immediately after baking by extraction with dichloromethane and sublimation in vacuo ( ). Application of aroma extract dilution analysis 6) to the acid-free crust extract led to the detection of 31 odorants. After separation and enrichment, these compounds were identified by comparison of the MS/EI, MS/Cl and retention data on two columns of different polarity to reference compounds. Aroma quality was also assessed. The results of the identification experiments (Table I) revealed that 2(E)-none-nal (No. 1), followed by 2(E),4(E)-decadienal (No. 2) and 3-methyl-butanal (No. 3) showed the highest FD-factors in the crust of the chemically leavened bread. Additionally l-octen-3-one, 2(Z)-nonenal, 2(E),4(E)-nonadienal and an unknown compound with a metallic odor contributed high FD-factors to the overall flavor (For a discussion of FD-factors, see Chapter by Schieberle and Grosch, this book). 

Somewhat surprising is the occurrence of the tricarbonyl->/3 2-2,6-cyclo-nonadiene-l-yl-manganese complexes 126d and 126n, with methyl groups in 4,5, and 8 and 1,3,5,5, and 7 positions, respectively, during the photoreaction... 

Methyl octine carbonate Methyl heptine carbonate c/.s-3-Hexenyl methyl carbonate Nonadienal Parmavert Violet leaf absolute Liffarome Phenyl acetaldehyde glyceroacetal Fiorivert... 

Green tea (Sencha) (Z)-1,5-Octadien-3-one (129), 4-methyl-4-sulfanyl-2-pentanone (130), methional, (2E,6Z)-2,6-nonadienal, 3-methyl-2,4-nonanedione (131), methyl ep/ -jasmonate, indole 148... 

Black tea (Darjeeling) (R)-Linalool, geraniol, (2 ,4 ,6Z)-2,4,6-nonatrienal, /3-damascenone, 2-methylbutanal, 2-methylpropanal, 3-methylbutanal, 3-methyl-2,4-nonanedione, (2f,6Z)-2,6-nonadienal 149... 

Ethyl 2-methylene-3-phenylpropionate, 80 3-Ethyl-7-methyl-frans,c/r-2,6-nonadiene-l-ol, 295... 

CIC Vitamin C (300 mg/100 g fmit), citric acid and malic acid are responsible for the clean acidic taste of the fresh fruit. A high enzyme activity of a lipoxygenase produces high amounts of (E)-2-hexenal, hexanal and (E)-2-hexenol, all fruity green notes, characteristic of green apples. The cut surfaces develop at prolonged standing 2-heptenal, 2,4-nonadienal and l-octen-3-one, responsible for stale, fatty odour. Methyl butyrate and ethyl butyrate impart the ripe, fruity, estery, fresh, juicy impression. 

The aromas associated widi very fi esh fish are usually mild, delicate and fi esh (53,54), and generally described as green (hexanal), melon-like ((E,Z)-3,6-nonadienal), iodine-like (bromophenols). Fresh fish and seafood aromas are due to volatile carbonyls and derive fi om lipoxygenase catalyzed oxidation of polyunsaturated fatty acids. The oxidation of Eicosapentaenoic acid (C20 5) leads to C5 to C9 alcohols, aldehydes, ketones and hydrocarbons. The formation of methyl mercaptan, dimethyl sulfide and dimethyl disulfide in fi esh fish at the time of harvest has been reported by Shiomi et al. (55). Although these compounds are usually associated with fish deterioration, they contribute to the fi esh aroma ch cter at low concentrations. For instance, dimethyl sulfide is... 

Dimethyl-9-cyclobulm-(l)-yl-nonadien-(2,5) (IX) entsteht nur bei direkter Belichtung, exo- und endo-5-Methyl-l-vinyl-5-[4-m.ethyl-penten-(3)-yl]-bicyclo[2.1.1]hexan (VII, VIII)... 

Nonadienal, 3-ethyl-7-methyl-, (EZY juvenile hormone synthesis from, 30... 

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