Detection of Elusive Chloro- and Bromo Substituted Ozonides by nucleophilic substitution reactions

Ozonolyses of 2,3-dichloro-2-butene ( 4 ), 4,5-dichloro-4-octene ( 9 ) and 2,3-dibromo-1,4-dichloro-2-butene ( 12 ) on polyethylene gave the corresponding ozonides 5 , 10 and 13a , respectively, which could not be isolated or unequivocally identified. Their identity could be proven, however, via substitution of the chloro- or bromo substituents at the ozonide rings by stabilizing substituents and subsequent isolation of the substituted ozonides 6 , 11 , 13b and 13c . Ozonolysis of 2,3-diacetoxy-2-butene ( 14 ) on polyethylene, in dichloro methane and in pentane gave mixtures of 16 and 17 but not ozonide 6 .