Synthesis of N-methylcarbazoles from N-(2-iodoaryl)-N-methylanilines in the presence of potassium tert-butoxide and iron(II) bromide
An effective and accessible method was developed for the preparation of N-methylcarbazoles from N-(2-iodoaryl)-N-methylanilines. Cyclization occurred in the presence of potassium tert-butoxide and iron(II) bromide by a mechanism of radical homolytic substitution. Two regioisomers were formed in cases when the aryl groups had meta- substituents relative to the amino group.