中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
---|---|---|---|---|
—— | 2,6-bis(3,4-diethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrrol-2-yl)pyridine | 1361318-35-5 | C33H49B2N3O4 | 573.392 |
Expanded pyriporphyrins with five and ten nitrogens were prepared in 67% and 6.5% yield, respectively, by the reactions of bis(azafulvene) and dipyrrylpyridine. The minimum 17-membered non-aromatic macrocycle made of four pyrroles and one pyridine is highly non-planar in comparison with orangarin that contains a tripyrrole unit instead of a dipyrrylpyridine unit. This highly non-planar ring structure is basically unchanged in the complex with trifluoroacetic acid (TFA) where carboxylate anions are bound on both sides of the macrocyle plane by multiple hydrogen bondings. This monopyridine-tetrapyrrole hybrid macrocycle was able to act as a dianionic ligand for various metal ions including lanthanide ions. In contrast to the reported figure eight type X-ray structure of turcasarin that is a double sized macrocycle of orangarin, the pyridine-containing macrocycle analog of the same 34-membered ring size isolated in this study was found not to take a figure eight type conformation as evidenced by X-ray crystallography of the tetracation with TFA anions.