Isolated double bond

The addition of an alkyl radical to an ethylenic linkage, as demonstrated by the conversion of 45 to 46, can be explained in terms of at least two mechanisms. The first is that carbonyl activation is a prerequisite for the initial attack of the alkyl radical upon the double bond, which implies that the addition is closely related to the Michael reaction.9 If this view is correct, then an isolated double bond will be inert to an initial radical addition of the type 57 — 58. Alternatively, one can argue that any suitably placed double bond, isolated or otherwise, can be attacked by an alkyl radical in these terms the ultimate product formed depends on the energy of the intermediate radical. 

Many functional groups, such as halogen, acetal, ketone, and acetate, and in some cases alcohol, aldehyde, and amide, can survive during the Kolbe decarboxylation [44], Double bonds isolated from the carboxylic acid moiety are usually not affected under the... 

The chemical properties of a diene depend upon the arrangement of its double bonds. Isolated double bonds exert little effect on each other, and hence each reacts as though it w/ere the only double bond in the molecule. Except for the consumption of larger amounts of reagents, then, the chemical properties of the non-conjugated dienes are identical with those of the simple alkenes. 

Zumbrunn, A., Uebelhart, P. and Eugster, C.H. 1985. HPLC of carotenes with y-end groups and (Z)-configuration at terminal conjugated double bonds, isolation of (5Z)-lycopene from tomatoes. Helv. Chim. Acta. 68 1540-1542. 

Purpurosamine B (382), a seven-carbon atom sugar component of the antibiotic gentamicin C2, was synthesized from 6-acetyl-5,6-dihydio-2-methoxy-2H-pyran (333, R = Me). Oximation of the keto group, reduction of the oxime to the corresponding amine, and N-acetylation gave two stereoisomeric N-acet-amides. For further synthesis the erythro stereoisomer (380) was taken. Further steps involved the epoxldation of the double bond, isolation of the manno epoxide, and its reduction to methyl 6-acetamido-3,4,6,7-tetradeoxy-a-DL-araI)i>io-heptopyranoside (381). Oxidation of the 2-OH group, oximation of the ketone, and reduction of the oxime followed by acetylation gave methyl N,N -diacetyl-a-DL-purpurosaminide B, which was hydrolyzed to N,N -diacetyl-DL-purpuro-samine B (383). 

Fourier transform IR measurements were used to investigate PVDF films which had been irradiated by means of heavy ions (krypton ions) and electrons. Irradiation with krypton ions was carried out in the presence of helium, hydrogen, deuterium and oxygen. Triple bonds were characteristic of krypton ion irradiation. Double bonds (isolated and conjugated) occurred with both types of irradiation but concentrations were higher with the krypton radiation. The results, including the role of oxygen on the chemical modifications, were discussed. 36 refs. 

All types of carbon-carbon double bonds - isolated (e.g., propene), conjugated (e.g., butadiene) and cumulative (e.g., allene) - are reactive (Scheme 2.229) [1780]. The size of the substrate seems to be of little importance since steroids [1781] and... 

Isolated dienes have isolated double bonds isolated double bonds are separated by more than one single bond. 

Because this compound contains two identical substituents, step 5 of the naming procedure applies. Use the prefix di-. In addition, indicate the position of each substituent with a number separated by a comma. Because this compound is an alkene, specify the position of the double bond, isolated by hyphens, just before the base name. 

Two a bonds separate two double bonds = isolated diene... 

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