Nonane-4,6-dione

Bromobutane, condensation with 2,4-pentanedione to give 2,4-nonane-dione, 47, 93... 

The 2,4-dien-l-one system (203) is unusually prone to nucleophilic addition, giving the 3a,5a-epoxyketone (204) in aqueous alkaline solution, or the bicyclo-[3,3,l]nonane-dione analogue (205) with acetone and an acidic catalyst. 

Preparation and storage of products from both oilseeds is often inhibited by rancidity and bitter aroma defects caused mostly by volatile aroma active carbonyl compounds, e. g., (Z)-3-hexenal, (Z)-l,5-octadien-3-one and 3-methyl-2,4-nonan-dione. The rancidity-causing compounds are formed through peroxidation of linolenic acid, accelerated by the enzyme lipoxygenase and/or by hem(in) proteins (cf. 3.T.2.2). Furan fatty acids are the precursors in the case of the dione (cf. 14.3.2.2.5). Lipid peroxidation is also involved in the formation of another very potent odorant, 2-pentylpyridine, which produces grassy aroma defects in soybean products. Defatted soybean protein isolates contained 60-510 pg/kg of this compound, which with an odor threshold... 

Octahydrobicyclo[4.3.0]nonane-3,4-dicarboxylic imide CA name) decahydrocydopent[/]isoindole-l,3-dione (fusion name)... 

Acylation of the enamine (113) with a,/9-unsaturated acid chlorides has been shown (57) to give bicyclo(3.3.1)nonan-2,9-diones. Acryloyl ehloride on reaction with the enamine (113) and subsequent hydrolysis gave bicyelo-(3.3.1)nonan-2,9-dione (123). Mechanistic studies suggest that C alkylation by the olefin precedes acylation (87). 

An interesting variant of this reaction is the formation of 2-thiaadamantane-4,8-dione by hydrolysis of the reaction product of the bispyrrolidine enamine of bicyclo[3.3.1]nonane-2,6-dione with sulfur dichloride (106). 

Bicyclof 3.3.1 ]nonane-2,6-dione (10) A solution of 10 g of Meerwein s ester, 30 ml of glacial acetic acid, and 20 ml of 6 A hydrochloric acid is heated under reflux for 10 hours. The solution is then carefully distilled under aspirator pressure until all volatile materials (water and acetic acid) are removed. The solid residue is distilled at 129-131°/4 mm to afford the product. It may be recrystallized from benzene giving about 3 g of bicyclo-[3.3.1]nonane-2,6-dione, mp 138-140°. 

Succinic anhydride is dimerised to 1,6-dioxaspiro [4.4] nonane-2,7-dione by heating with sodium hydroxide. Modification of an existing procedure by adding further sodium hydroxide after the initial reaction led to a severe exothermic reaction after heating for some 30 h which fused the glass flask to the heating mantle, probably at a temperature approaching 550°C. The reason for this was not known [1], At elevated temperatures and under influence of alkali, succinic acid condenses decarboxylatively beyond the dimeric spiroacetal, sometimes explosively. Contamination of the anhydride with base is to be avoided [2],... 

Nonan-2-ol Decanoic acid Decane-2,5-dione 3-Methylphenol... 

Chinese chemists have reported the synthesis of pentacyclo[4.3.0.0 , 0 ]nonane-2,4-bis(trinitroethyl ester) (88). This compound may find potential use as an energetic plastisizer in futuristic explosive and propellant formulations. The synthesis of (88) uses widely available hydroquinone (81) as a starting material. Thus, bromination of (81), followed by oxidation, Diels-Alder cycloaddition with cyclopentadiene, and photochemical [2 - - 2] cycloaddition, yields the dione (85) as a mixture of diastereoisomers, (85a) and (85b). Favorskii rearrangement of this mixture yields the dicarboxylic acid as a mixture of isomers, (86a) and (86b), which on further reaction with thionyl chloride, followed by treating the resulting acid chlorides with 2,2,2-trinitroethanol, gives the energetic plastisizer (88) as a mixture of isomers, (88a) and (88b). Improvements in the synthesis of nitroform, and hence 2,2,2-trinitroethanol, makes the future application of this product attractive. 

Kinetics and mechanisms of complex formation have been reviewed, with particular attention to the inherent Fe +aq + L vs. FeOH +aq + HL proton ambiguity. Table 11 contains a selection of rate constants and activation volumes for complex formation reactions from Fe " "aq and from FeOH +aq, illustrating the mechanistic difference between 4 for the former and 4 for the latter. Further kinetic details and discussion may be obtained from earlier publications and from those on reaction with azide, with cysteine, " with octane-and nonane-2,4-diones, with 2-acetylcyclopentanone, with fulvic acid, and with acethydroxamate and with desferrioxamine. For the last two systems the various component forward and reverse reactions were studied, with values given for k and K A/7 and A5, A/7° and A5 ° AF and AF°. Activation volumes are reported and consequences of the proton ambiguity discussed in relation to the reaction with azide. For the reactions of FeOH " aq with the salicylate and oxalate complexes d5-[Co(en)2(NH3)(sal)] ", [Co(tetraen)(sal)] " (tetraen = tetraethylenepentamine), and [Co(NH3)5(C204H)] both formation and dissociation are retarded in anionic micelles. 

Non-8-en-4-olide, 3(R)-7(R)-epoxy-4(R)-8-dimethyl Lf 0.002NT349 Nonacosane-8-lO-dione Stigma Nonan-2-ol, 3-3-5-trimethyl-8-iso-propyl-4-9-dioxa-bicyclo-(3.3.1) Lf ... 

The n-7t Cotton effects of 3,8-di-tm-butylspiro[4.4]nonane-l,6-diones (2 and 3) are mainly due to cyclopentanone ring chirality imposed by the bulky fer -butyl substituent, although the effect of interaction between the carbonyl groups also seems to contribute38. 

Nearly all examples of epoxidation of alkylidenecyclobutanes involve 3-chloroperoxybenzoic acid.15 58-70 This is because the conditions are mild, the workup is easy and few byproducts are formed. Generally, dichloromethane or chloroform is used as solvent. Solid sodium hydrogen carbonate is occasionally added to avoid acid-catalyzed rearrangement of the spiro compound. For example, 6-isopropylidene-l,4,4-trimethylbicyclo[3.2.0]heptan-3-one reacted with 3-chloroperoxybenzoic acid and sodium hydrogen carbonate to give 2,2,3, 3, 6-pentamethyl-spiro[3-oxabicyclo[4.2.0]octane-8,2 -oxirane]-4-one (4) in quantitative yield. However, without the use of sodium hydrogen carbonate, substantial amounts of 2,2,6,9,9-pentamethyl-3-oxa-bicyclo[4.3.0]nonane-4,8-dione (5) and 2,2,6,8,8-pentamethyl-3-oxabicyclo[4.3.0]nonane-4,9-dione (6) were also formed.15-64... 

The homocubane bridgehead acetate 21 is extremely base labile, furnishing 1 -bromotetracy-clo[4.3.0.02 03,8]nonane-4,9-dione 9,9-ethylene acetal (22) in almost quantitative yield upon treatment with a solution of sodium methoxide in methanol.57 Likewise, 1-bromotetracy-clo[4,3.0.02 5.03,8]nonan-4-one (24) is obtained from an analogous acetate 23.57... 

Bicyclo[5.2.0]nonane-l,7-diol was oxidized by potassium periodate in water at room temperature to yield cyclononane-1,4-dione (6). 56... 

Various attempts to hydrolyse 9-ethylenedioxybicyclo[3.3.1]nonane-3,7-dione under acid conditions resulted only in the formation of either 5-hydroxyindan-2-one (HCl/AcOH 14% yield) or a mixture of the indanone (13%) and 7,9-bis(ethylenedioxy)bicyclo[3.3.1]nonan-3-one (13% 10% aqueous HC1). 

Succinic anhydride is dimerised to 1,6-dioxaspiro [4.4] nonane-2,7-dione by heating with sodium hydroxide. Modification of an existing procedure by adding further... 

Photochemically induced transannular ring closure of bicyclo[3-3.1 -nonane-3,7-dione to 3,7-noradamantane diol is illustrated in Eq. (38)12S). 

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