A 1,5-Naphthyridine-Fused Porphyrin Dimer: Intense NIR Absorption and Facile Redox Interconversion with Its Reduced Congener

作者：Fujimoto Keisuke; Osuka Atsuhiro^*

来源：Chemistry - A European Journal, 2018, 24(25): 6530-6533.

DOI：10.1002/chem.201800854

• 1,5-naphthyridine
• NIR absorption
• platinum
• porphyrin
• redox activity

Pt-II-catalyzed cyclization of beta-to-beta ethynylene-bridged meso-amino Ni-II porphyrin dimer 4 followed by oxidation with PbO2 afforded 1,5-naphthyridine-fused porphyrin dimer 5 in good yield. This dimer possesses a redox-active 1,4-diazabutadiene linkage that is interconvertible with its reduced 1,2-diaminoethene linkage upon treatments with NaBH4 or PbO2. The dimer 5 exhibits an intense NIR absorption and a narrow HOMO-LUMO gap with a remarkably low reduction potential mainly due to effective bonding interactions in the LUMO through the 1,4-diazabutadiene linkage. In contrast, the reduced dimer 7 is fairly electron-rich with high HOMO energy and shows a relatively large HOMO-LUMO gap compared to that of 5.

• 出版日期2018-5-2