|Budget Amount *help
¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1998 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1997 : ¥2,100,000 (Direct Cost : ¥2,100,000)
Dimeric porphyrins have been drawing much attention as structural units for multi-electron redox systems. Two porphyrins are linked by covalent bonding between substituents at the porphyrin periphery or by ligand bonding between central metals, as approaches by organic chemistry and coordination chemistry, respectively. Since structural factors such as inter-ring distance and orientation between two porphyrin plane make great influence on the multi-electron redox functions, this work was intended to create new bisporphyrin framework. The research achievements are as following.
(1) We had already found that unusual (CH=CH-N,N')-link can be made between pyrrole nitrogen s of two porphyrins by one-step reaction between Co(III) porphyrin and acetylene. We have established experimental conditions and yields for combinations of various porphyrins in this coupling reaction. (2) We have prepared various mixed binuclear complexes of bisporphyrin with combinations of Zn, Cu, and Co in good yields and determined their spectroscopic properties and X-ray crystal structure. (3) We have shown that unusual tris- and tetrakis-porphyrins metallated with Zn, Cu, Co, and Fe are easily synthesized. In particular, a Fe-O-Fe link was readily constructed to lead to mixed-metal tetrakisporphyrins.
The bisporphyrins with unusual spacers between pyrrole nitrogens have been shown to be useful as the building block for layered porphyrin systems.