ortho-Effect in some aromatic ethers, sulphides, and sulphoxides under electron impact

Abstract

An ortho-effect has been found for the loss of Cl· from the molecular ions of chlorodiphenyl ethers, sulphides, and sulphoxides. This was not observed for the corresponding sulphones and o-chlorophenyl benzyl ether, owing to the competition of other, energetically more favourable, reactions. The reaction due to the ortho-effect in the molecular ions of o-chlorodiphenyl ether, sulphide, and sulphoxide were the lowest-energy processes, competing successfully with rearrangements. In the case of the three chlorodiphenyl sulphides, there was indication for a different structure of the ortho-(M– Cl)^⌉+ ion from those of the meta- and para-isomers. Chlorine scrambling in simple disubstituted benzenes is discussed in view of the results.