Highly diastereoselective synthesis of a novel functionalized benzocyclotrimer

The high yielding synthesis of a novel benzocyclotrimer is herein presented. The syn-diastereomer is obtained as major product, presumably in virtue of the presence of an oxa-bridge of the bicylic components. The three oxa-bridges can be used for further functionalization, as well as the six bromine atoms of the three aromatic rings, as demonstrated in the aromatization of a mixture of anti-1 and syn-1 (3:7) leading to trinaphthylene.