Limonene, ozonolysis

The rate coefficients of limonene ozonolysis, evaluated at the BH and HLYP/cc-pvdz level, and the theoretical Arrhenius expression were in reasonable agreement with the experimental values and correctly described the initial steps of ozonolysis. The ozonide formation was highly exothermic, and the decomposition channels had similar free energies of activation, AG, indicating that there was no primary pathway for ozonide decomposition. ... 

Fig. 10 SOA product volatility distributions for a-pinene and limonaketone in dark green and mass yields vs Cqa as dark green curve. Precursors with similar volatility, structure, and chemistry have similar yields. Product volatility distribution and yields fOTD-limonene ozonolysis are shown as light green bars and a light green curve (and gray data points). Oxidation of the additional exocyclic double bond in limonene results in substantially less volatile SOA products and correspondingly higher SOA yields...

Zhang JY, Hartz KEH, Pandis SN, Donahue NM (2006) Secondary organic aerosol formation from limonene ozonolysis homogeneous and heterogeneous influences as a function of NOx. JPhys Chem A 110(38) 11053-11063... 

In order to establish the correct absolute stereochemistry in cyclopentanoid 123 (Scheme 10.11), a chirality transfer strategy was employed with aldehyde 117, obtained from (S)-(-)-limonene (Scheme 10.11). A modified procedure for the conversion of (S)-(-)-limonene to cyclopentene 117 (58 % from limonene) was used [58], and aldehyde 117 was reduced with diisobutylaluminium hydride (DIBAL) (quant.) and alkylated to provide tributylstannane ether 118. This compound underwent a Still-Wittig rearrangement upon treatment with n-butyl lithium (n-BuLi) to yield 119 (75 %, two steps) [59]. The extent to which the chirality transfer was successful was deemed quantitative on the basis of conversion of alcohol 119 to its (+)-(9-methyI mande I ic acid ester and subsequent analysis of optical purity. The ozonolysis (70 %) of 119, protection of the free alcohol as the silyl ether (85 %), and reduction of the ketone with DIBAL (quant.) gave alcohol 120. Elimination of the alcohol in 120 with phosphorus oxychloride-pyridine... 

Norgaard, A.W., Nojgaard, J.K., Larsen, K., Sporring, S., Wilkins, C.K., Clausen, P.A. and Wolkoff, P. (2006) Secondary limonene endo-ozonide a major product from gas-phase ozonolysis of R-(+)-limonene at ambient temperature. Atmospheric Environment, 40, 3460-6. 

There are some interesting examples of selective ozonolysis in the terpene field. Limonene is ozonized at the 8,9- double bond in preference to the 1- double bond. This is indicated by the fact that the amount of formaldehyde found is almost equal to the amount of ozone introduced, up to 1 mole. In like manner, terpinolene yields acetone in an amount nearly equal to the ozone passed, up to 1 mole. -Pinene should add ozone readily and form formaldehyde and nopinone on ozonolysis. Practically none of these products can be obtained by ordinary ozonolysis techniques. The hydrogens alpha to the double bond, with probable additional activation from the general strain of the system, are so active to peroxidation by oxygen that little ozonide is formed, because of the large excess of oxygen present. 

Carveol is also expected to be very reactive towards OH, O3, and NO3, probably at a rate at least as great as the compounds with similar stracture such as limonene (Calvert et al., 2000). Therefore, its atmospheric lifetime is estimated to be less than 1 h. The only product observed by Nunes et al. (2005) in their study of the ozonolysis of carveol is formaldehyde with a production yield of 19 0.8%. 

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