Abstract Reactions of 3-cyclohexenecarbaldehyde, 6-methyl-3-cyclohexenecarbaldehyde, bicyclo [2.2. 1]-hept-5-ene-endo-2-carbaldehyde, benzaldehyde with 1, 2-propanediol, 3- chloro-1, 2-propanediol gavethe corresponding 2, 4-substituted 1, 3-dioxolanes. Their reactions with peroxyacetic acid, bromine, dichloro-carbene, and nucleophiles were studied. The effect of the substituents in the diol and aldehyde on their relative reactivity is ...