Ozonolysis of cis- and trans-1,4-dichlorobut-2-ene. Non-concerted formation of primary ozonides

Abstract

The ozonolysis of cis- or trans-CH₂Cl·CHCH·CH₂Cl (1) performed at –10 °C in a participating solvent (CD₃OD) has been found to lead to non-concerted formation of primary ozonides (9). The heterolysis of these unusually stable primary ozonides to the corresponding alkoxy peroxide (11) and aldehyde (12) was monitored and the data have been tentatively rationalized by assuming neighbouring halogen participation which actually increases the stability of the Criegee zwitterionic intermediate (6).