Boron complexes of oxasmaragdyrin, a core-modified expanded porphyrin.

We report the synthesis of first examples of BF(2) and B(OR)(2) complexes of oxasmaragdyrin, the expanded core-modified porphyrin, in decent yields under very simple reaction conditions at room temperature. The boron complexation of oxasmaragdyrin alters the electronic properties of the macrocycle significantly as evident by various spectroscopic techniques. Our preliminary studies indicated that the B(OH)(2)-smaragdyrin complex can act as a selective neutral fluoride ion sensor.