Synthesis of 1,4,5,16-tetrahydroxytetraphenylene

This paper concerns the synthesis of 1,4,5,16-tetrahydroxytetraphenylene, which may function as a building block for the construction of molecular scaffolds. The synthesis of 1,4,5,16-tetrahydroxytetraphenylene was realized by stepwise Diels–Alder reactions to form two benzene rings using 1,10-dimethoxydibenzo[a,e]cyclooctene as a precursor. This key intermediate, in turn, could be obtained by photo-rearrangement of its corresponding barrelene.