Hydrocarbons ozone adducts

Hydrocarbon CXXXIV was prepared from abieta-6,8-diene (CXXXV) by the following route. Reaction with maleic anhydride gave the adduct CXXXVI, whose dimethyl ester was ozonized to give CXXXVII in 35% yield. Oxidation of the latter with H2O2-BF3 gave the keto diester CXXXVIII in 60% yield. The diacid of CXXXVIII was subjected to oxidative bis decarboxylation with lead tetraacetate in pyridine to afford the keto olefin CXXXIX. Hydrogenation of CXXXIX over palladium/... 

Addition of ozone to hexakis(tTifluoromethyI)benzvalene gives the ozonide (183) as a stable yellow liquid. Photolysis of (183) at low temperature in a hydrocarbon matrix led to extrusion of trifluoroacetic anhydride and formation of the syn-dimer (184) of tetrakis(trifluoromethyl)cyclobutadiene (185). Irradiation of (183) in the presence of ethyl azodicarboxylate gives the 1 1 adduct of (185) and ethyl azodi-carboxylate. 

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