Accession Number : AD0676427

Title :   RATES OF REACTIONS OF OZONE WITH CHLORINATED AND CONJUGATED OLEFINS,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF APPLIED CHEMISTRY

Personal Author(s) : Williamson,D. G. ; Cvetanovic,R. J.

Report Date : 16 MAR 1968

Pagination or Media Count : 6

Abstract : The absolute values of the second-order rate constants for the reactions of ozone with chloroethylenes and allyl chloride were determined in carbon tetrachloride solution at room temperature. The rate of ozone attack decreases strongly as the number of chlorine atoms in the olfefin molecules is increased. The large variation in the values of the rate constants for the chloroethylenes, from 1.01/mole/sec for C2Cl4 to 1200 1/mole/sec for C2H3Cl, is believed to be primarily due to a predominantly electrophilic role of ozone in its reactions with these olefins. A pronounced additional trend is shown by the three isomeric dichloroethylenes: trans-1,2-C2H2Cl2 is about 16 times more reactive than cis-1,2-C2H2Cl2, while 1,1-C2H2Cl2 is the least reactive of the three isomers. These trends are discussed in terms of the electronic and steric effects and are compared with the behavior of other 1,3 dipoles in their cycloadditions to olefins. Relative rates of ozonation of 1,3-C4H6 and styrene were determined by competition with 1-pentene. The two conjugated olefins do not show a strongly increased reactivity and in this respect differ from the behavior reported for some other 1,3-dipolar cycloadditions. (Author)

Descriptors :   (*ALKENES, OXIDATION), (*HALOGENATED HYDROCARBONS, OXIDATION), (*OZONE, REACTION KINETICS), CHLORINE COMPOUNDS, MOLECULAR ISOMERISM, ADDITION REACTIONS, OXYGEN HETEROCYCLIC COMPOUNDS, CANADA

Subject Categories : Organic Chemistry
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE