Mechanism of ozonolysis

The following questions pertain to the details of mechanism of ozonolysis under modified conditions. 

FIGURE 8-2 Mechanism of ozonolysis. A, Criegee zwitterion B, aldehyde C, ozonide. 

Mass spectrometry has been used to investigate the mechanism of ozonolysis <79JOC3i85,80JA4763) and to study the gas-phase reaction of furans with singlet oxygen in which endoperoxides are intermediates. 

SCHEME 1. Mechanism of ozonolysis. Reproduced by permission of Wiley-VCH Verlag GmbH from Reference 15... 

T0For a discussion of the mechanism of ozonolysis of triple bonds, see Prvor Govindan Church J. Am. Chem. Soc. 1982, 104. 7563. 

Chapman JR (1985) Practical organic mass spectrometry John Wiley, Chichester, 197 pp Cnegee R (1975) Mechanism of ozonolysis Angew Chem Int Ed Engl 14 745-751 Deslongchamps P, Atlam P, Frehel D, Malaval A, Moreau C (1974) The oxidation of acetals by ozone Can J Chem 52 3651-3664... 

T he Criegee (1) mechanism of ozonolysis postulates that unsymmetrical olefins should give two zwitterions and two carbonyl compounds and hence postulates the possible formation of three different ozonides. This prediction has now been realized in a number of cases (2-9). It has also been shown that in many cases the ozonide stereoisomer ratio depends upon olefin stereochemistry in both normal (3, 6-12) and cross (6-9) ozonides. Since the original Criegee mechanism did not provide for these stereochemical results, a number of additional suggestions for the mechanism have been made (6,9,13, 14), all of which retain the fundamentals of the Criegee mechanism. 

We have attempted to gain further information concerning the mechanism of ozonolysis by using conditions where ozonolysis might be... 

In this case the total yield of diperoxides was 27.6%. We are still trying to improve the yield of diperoxide products from these reactions hence these yields should not be regarded as optimum values. At any rate, we have established that cross diperoxides can be formed so that we have an additional probe with which to examine the mechanism of ozonolysis problem. 

During the past seven or eight years some excellent and novel studies have cast doubt upon the Criegee mechanism as the sole mechanism of ozonolysis. All of the newer mechanisms proposed, however, have ac-... 

The product distribution and mechanism of ozonolysis differ when the oxidant is adsorbed on silica gel. When dried silica gel was used, Besten and Kinstle found that the products were similiar to those... 

The reactions of O3 with C3H6, 9 and 10, were based on a review of the mechanism of ozonolysis by Murray (15). The accepted mechanism in the gas phase is similar to that commonly referred to as the Criegee mechanism in the liquid phase. The attack of O3 on C3H6 is electrophilic, and Vrbaski and Cvetanovic (16) have correlated the electrophilic behavior with that of oxygen atom-olefin reactions. Both reaction rates correlate with the ionization potentials of a series of olefins. 

Criegee, R. (1975). Mechanism of ozonolysis. Angew. Chem. Int. Ed. Engl. 14, 745-751. Cronn, D. R., R. J. Charlson, R. L. Knights, A. L. Crittenden, and B. R. Appel (1972). A Survey of the molecular nature of primary and secondary components of particles in urban air by high resolution mass spectroscopy. Atmos. Environ. 11, 929-937. 

---