MnO2 instead of quinones as selective oxidant of tetrapyrrolic macrocycles

Porphyrins and chlorins were generated through dehydrogenation of the corresponding porphyrinogen and bacteriochlorin precursors using activated manganese dioxide and focused microwave irradiation. The application of this inexpensive heterogeneous oxidant under microwave heating conditions, instead of the quinones usually employed in conventional methodologies, allowed short reaction times, simple overall work-ups and good yields.