N-Heptanol oxidation

Eq. 4.54 shows the reaction of n-heptanol (151) with Pb(OAc)4 under high-pressured carbon monoxide with an autoclave to generate the corresponding 8-lactone (152). This reaction proceeds through the formation of an oxygen-centered radical by the reaction of alcohol (151) with Pb(OAc)4,1,5-H shift, reaction with carbon monoxide to form an acyl radical, oxidation of the acyl radical with Pb(OAc)4, and finally, polar cyclization to provide 8-lactone [142-146]. This reaction can be used for primary and secondary alcohols, while (3-cleavage reaction of the formed alkoxyl radicals derived from tertiary alcohols occurs. 

Similar experiments were carried out in which drops that were mixtures of /i-decane and various alcohols were injected into dilute solutions of a zwitterionic (amine oxide) surfactant. Here, too, the lamellar phase was the first intermediate phase observed when the system was initially above the PIT. However, with alcohols of intermediate chain length such as /i-heptanol, it formed more rapidly than with oleyl alcohol, and the many, small myelinic figures that developed broke up quickly into tiny droplets in a process resembling an explosion.The high speed of the inversion to hydrophilic conditions was caused by diffusion of n-heptanol into the aqueous phase, which is faster than diffusion of surfactant into the drop. The alcohol also made the lamellar phase more fluid and thereby promoted the rapid breakup of myelinic figures into droplets. Further loss of alcohol caused both the lamellar phase and the remaining microemulsion to become supersaturated in oil, which produced spontaneous emulsification of oil. 

Mixtures of aldehydes with surfactants are active in preventing corrosion, in particular in the presence of mineral or organic acids [646]. The aldehyde may be trans-cinnamaldehyde. The surfactant may be N-dodecylpyridinium bromide or the reaction product of trimethyl-1-heptanol with ethylene oxide [645]. Such aldehyde and surfactant mixtures provide greater and more reliable corrosion inhibition than the respective compositions containing aldehydes alone. 

Figure 4.6. The GC/MS-EI (70eV) chromatogram recorded in SCAN mode of free aroma compounds of a Muscat grape skins extract. I.S., internal standard (1-heptanol) peak 1. linalool peak 2.1 rans -p y ra n I i n a I oo I oxide peak 3. cis-pyranhnalool oxide peak 4. nerol peak 5. geraniol peak 6. Ho-diendiol I peak 7. Ho-diendiol II peak 8. hydroxycitronellol peak 9. 7-hydroxy geraniol peak 10. ( )-geranic acid.

Methods of determination of the configuration of bicyclo[2,2,l]-heptanols have been reviewed. The platinum-catalysed oxidation of bicyclo-[2,2,l]heptanediols, whose n.m.r. spectra are discussed, gives ° a number of different diketones and hydroxy-ketones. The n.m.r. spectra of adducts of cyclopentadiene with a-methyl-P-acetylacrylic acid, and of dimers of substituted cyclopentadienes, are noted. 

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