Low-Temperature Ozonolysis of 2-Alkenyl-1,1-dichlorocyclopropanes

Abstract

Low-temperature ozonolysis of 2-alkenyl-1,1-dichlorocyclopropanes under different conditions (O₃/MeOH–CH₂Cl₂–NaOH, O₃/MeOH or O₃/CH₂Cl₂–AcOH with subsequent treatment with semicarbazide hydrochloride) afforded the corresponding carbonyl and carboxy derivatives at different ratios, depending on the substrate structure and workup procedure. Peroxide products of ozonolysis of 1,1-dichloro-2-ethenylcyclopropane [3-(2,2-dichlorocyclopropyl)-1,2,4-trioxolane and (2,2-dichlorocyclopropyl)(methoxy)methyl hydroperoxide] turned out to be more stable than those derived from 1,1-dichloro-2-ethenyl-2-methylcyclopropane and were isolated in the pure state.