Synthesis of poly-substituted pyrroles starting from the Baylis–Hillman adducts

We synthesized poly-substituted pyrrole derivatives 4a–e, 7a–c and 10a–d from the reaction of phenacyl bromide and the aza-Baylis–Hillman adducts 1a–d or their rearranged derivatives 5a–e. The pyrroles were synthesized via the successive N-alkylation, Michael addition, elimination of p-toluenesulfinic acid and oxidative aromatization processes.