Abstract: The ozonolyses of 1, l-difluoroethylene and trifluoroethylene have been studied in CF2C1CFC12, CF2C12, and CF3CI. Ozonolysis of 1, l-difluoroethylene produces normal secondary ozonide and carbonyl fluoride as major products. Ethylene ozonide was detected in lower yield in the reactions carried out in CF2C12 and CF3C1. Results from aldehyde insertion experiments are in agreement with a preferred direction of cleavage of the ...