Citronellic acid

Further, d-citronellal, the corresponding aldehyde, may be converted into citronellic acid through its oxime and nitrile. Citronellic acid, when treated with thionyl chloride in benzene solution, yields a chloride of a chlorinated acid which is converted by the action of alcohol into the hydrochloride of ethyl citronellate, or hydrochloride of ethyl rhodinate,... 

Further evidence of the difference between rhodinol and citronellol is forthcoming, in that the former yields on oxidation an aldehyde, rhodinal, whose oxime does not yield citronellic acid nitrile when treated with acetic anhydride, nor citronellic acid when the nitrile is treated with alkalis, wheras citronellal, the aldehyde of citronellol, does yield the nitrile and citronellic acid. 

Citronellic acid, C Hj-. COOH, is the acid corresponding to the alcohol citronellol, and is present in the essential oil of Barosma jmlcliel-lum. It has the following characters —... 

Acetylation.—Gitronellal may be quantitatively estimated by the ordinary acetylation process i when the aldehyde is quantitatively converted into isopulegyl acetate, which is then determined by saponification with potash in the ordinary way. Dupont and Labaume have attempted to base a method for the separation of geraniol from citronellal in citron-ella oils on the fact that the citronellal oxime formed by shaking with hydroxylamine solution at the ordinary temperature is not converted into an ester by subsequent acetylation, but into the nitrile of citronellic acid which is stable towards" alkali during the saponification process. 

Zitronell-al, n, citronellal. -assure, /, citron-ellic acid, -ol, n. citronellol, -81, n, citron, ella oil. -saure, /, citronellic acid. Zitronen-ather, m. citric ester, -farbe, /. 

The adjacent iodine and lactone groupings in 16 constitute the structural prerequisite, or retron, for the iodolactonization transform.15 It was anticipated that the action of iodine on unsaturated carboxylic acid 17 would induce iodolactonization16 to give iodo-lactone 16. The cis C20-C21 double bond in 17 provides a convenient opportunity for molecular simplification. In the synthetic direction, a Wittig reaction17 between the nonstabilized phosphorous ylide derived from 19 and aldehyde 18 could result in the formation of cis alkene 17. Enantiomerically pure (/ )-citronellic acid (20) and (+)-/ -hydroxyisobutyric acid (11) are readily available sources of chirality that could be converted in a straightforward manner into optically active building blocks 18 and 19, respectively. 

A cursory inspection of key intermediate 8 (see Scheme 1) reveals that it possesses both vicinal and remote stereochemical relationships. To cope with the stereochemical challenge posed by this intermediate and to enhance overall efficiency, a convergent approach featuring the union of optically active intermediates 18 and 19 was adopted. Scheme 5a illustrates the synthesis of intermediate 18. Thus, oxidative cleavage of the trisubstituted olefin of (/ )-citronellic acid benzyl ester (28) with ozone, followed by oxidative workup with Jones reagent, affords a carboxylic acid which can be oxidatively decarboxylated to 29 with lead tetraacetate and copper(n) acetate. Saponification of the benzyl ester in 29 with potassium hydroxide provides an unsaturated carboxylic acid which undergoes smooth conversion to trans iodolactone 30 on treatment with iodine in acetonitrile at -15 °C (89% yield from 29).24 The diastereoselectivity of the thermodynamically controlled iodolacto-nization reaction is approximately 20 1 in favor of the more stable trans iodolactone 30. 

P-citronellene 605 f 612 (/Q-citronellic acid 232, 235 (/ )-citronellol 360 Claisen rearrangement 17, 87, 90, 137 f., 140, 142, 194 -, Johnson ortho ester variant see Johnson ortho ester Claisen rearrangement cobalt-mediated cyclization... 

Hydrogen peroxide Ketones, Nitric acid Ozone Citronellic acid See other cyclic peroxides... 

During work-up of the products of ozonolysis of R- and S-citronellic acids, a substantial quantity of the highly explosive trimeric acetone peroxide (3,3,6,6,9,9-hexamethyl-l,2,4,5,7,8-hexoxonane) was unwittingly isolated by distillation at 105-135°C to give the solid m.p. 95°C. The peroxide appears to have been produced by ozonolysis of the isopropylidene group in citronellic acid, and presumably the same could occur when any isopropylidene group is ozonised. Appropriate care is advised. 

Citronellic acid, 3352 Cyanoacetic acid, 1113 Diazirine-3,3-dicarboxylic acid, 1080 Diazomalonic acid, 1081... 

In a 50-mL, round-bottomed flask, equipped with a rubber septum and a magnetic stirring bar and filled with argon, are placed citronellic acid (112 mg, 0.658 mmol) and a solution of (R)-1-(1-naphthyl)ethylamine (140 mg, 0.818 mmol) (Note 29) in dry DMF (4 mL) (Note 5). To this mixture in an ice bath are added a solution of diethyl cyanophosphonate (224 mg, 1.37 mmol) (Note 30) in dry DMF (2 mL) and then dry triethylamine (0.1 mL). The mixture is stirred and the reaction is followed by TLC. When the carboxylic acid has been consumed, which takes approximately 2 hr at room temperature, the reaction mixture is dissolved in a mixture of benzene (5 mL) and ethyl acetate (5 mL). The mixture is washed successively with cold 5% hydrochloric acid,... 

C1 qHi gOg, were obtained by Harries Himmel (Ref 2) on treating citronellic acid, CtQH,802 (Ref 1), dissolved in CC14, with ozone. On evapn of CC14 a col syrup was obtained, which decompd on contact with w... 

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