Electron structure and substituent effects in o-,m-,p-IC6H4OCH3 iodoanisoles

The electronic structures and substituent effects in o-,m-,and p-iodoanisoles have been investigated by ultraviolet photoelectron spectroscopy(UPS).The observed UPS bands were analyzed by combining empirical arguments and theoretical methods.Owing to the electron-donating nature of both iodoand methoxy substituents,the first ionization potentials of the three iodoanisoles are lower than those of iodobenzene and anisole.The presence of the two substituents in iodoanisoles leads to an electronrich structure,which might contribute to the observed high reactivity of iodoanisoles in a number of organic reactions.