Mono(m-substituted) chloroacetyldiarylamines in the stollé reaction
The effect of substituted (OCH3, Cl) on the ratio of the isomeric N-aryloxindoles formed in the Stollé reaction from mono (m-substituted) chloroacetyldiarylamines was studied. It was shown by means of gas—liquid chromatography (GLC) and PMR spectroscopy that in the case of the methoxy group electrophilic substitution occurs only in the ring activated by the substituent. The presence of a halogen atom leads only to 1-(m-chlorophenyl)oxindole. The results show that high selectivity of the attack by the carbonium ion on the phenyl rings with electrondonor and electron-acceptor substituents is also retained in the case of intramolecular electrophilic substitution under conditions of kinetic control.