Pyrogallate‐Based Metal‐Organic Framework with a Two‐Dimensional Secondary Building Unit

Abstract We report a metal–organic framework (MOF) with a rare two‐dimensional (2D) secondary building unit (SBU). The SBU comprises mixed‐valent Fe 2+ and Fe 3+ metal ions bridged by oxygen atoms pertaining to the polytopic ligand 3,3′,4,4′,5,5′‐hexahydroxybiphenyl, which also define the iron‐oxide 2D layers. Overall, the anionic framework exhibits rare topology and evidences strong electronic communication between the mixed‐valence iron sites. These results highlight the importance of dimensionality control of MOF SBUs for discovering new topologies in reticular chemistry, and especially for improving electronic communication within the MOF skeleton.