Ozone complex with acetylene

Ozone also adds to the carbon-carbon triple bond of acetylenic compds, the usual products being diketones and carboxylic acids. In polynuclear aromatic compds, the various carbon bonds and atoms have different reactivities. The reaction with ozone is more complex and the compn of products is difficult to predict... 

Predict the structure of the van der Waals complex between ozone and acetylene. Indicate which frontier orbital interactions should be most important. How does your prediction compare with the experimental structure (Gillies, J. Z. Gillies, C. 

Predict the structure of the van der Waals complex between ozone and acetylene. Indicate which frontier orbital interactions should be most important. How does your prediction compare with the experimental structure (Gillies, J. Z. Gillies, C. W. Lovas, F. J. Matsumura, K. Suenram, R. D. Kraka, E. Cremer, D., J. Am. Chem. Soc., 1991, 113, 6408) ... 

At present, there is an opinion that the first stage of the reaction proceed by another pathway. First of all, the reaction for ethylene and acetylene proceeds through formation of an intermediate weakly-bound complex, which was determined experimentally and theoretically [12-14, 16, 18]. Similar complexes were determined by methods of quantum chemistry for ozone with cis- and trans-butene-2 [19]. In [20], by approximation of the restricted Hartree-... 

Another example demonstrating the difference in reactivity is the ozonolysis reactions of acetylene and ethylene. Ozonolysis of ethylene is a classical 1,3-dipolar cycloaddition reaction with an activation energy of 5 kcal/mol [106], whereas a larger activation energy of 11 kcal/mol was measured for the reaction of ozone with acetylene [107]. The 1,3-dipolar cycloaddition adduct, 1,2,3-trioxolene, has not been definitively observed as an intermediate involved in the acetylene ozonolysis. Nevertheless, according to the combined microwave and ab-initio calculation studies, the formation of similar van der Waals complexes in the course of ozonolysis has been established for both acetylene and ethylene [108]. 

New Applications of Tetracyanoethylene (TCNE) in Organic Chemistry, A. J. Fatiadi (1986). This review with 501 references deals with reactions of tetracyanoethylene used in organic synthesis. Information on molecular complexes, ozonization of alkenes and acetylenes, dehydrogenation and tricyanovinylation, reactions of TCNE oxide, reactions with ketones and diketones, synthesis of heterocycles and cationic polymerizations are included in this survey. Some industrial and analytical applications are also discussed. 

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