We have developed a simple method for the chemoselective aromatization of tetrahydro‐β‐carboline with selective nondeallylation O‐allyl groups in the presence of iodine (100 mol %) in dimethyl sulfoxide/H2O2. A convergent approach toward the oxidative aromatization with selective deallylation (deprotection) of O‐allyl‐tetrahydro‐β‐carboline using iodine in dimethyl sulfoxide/HCl has been described. The present protocol contains cheap catalyst, easy work up, normal reaction conditions, and high selectivity. [ABSTRACT FROM AUTHOR]