2000 Fiscal Year Final Research Report Summary
Synthesis and Characterization of New porphyrins and Porphyrin Derivatives with Fluorine.
Project/Area Number |
11680596
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Bioorganic chemistry
|
Research Institution | Fukushima National College of Technology |
Principal Investigator |
AOYAGI Katsuhiro Fukushima National College of Technology, Department of Chemistry and Biochemistry Professor, 物質工学科, 教授 (40150940)
|
Project Period (FY) |
1999 – 2000
|
Keywords | Porphyrin / Meso position / Trifluoromethyl group / Photochemical reaction / Organic synthesis / Redox potential / Energy calculation / Distortion |
Research Abstract |
5, 10, 15, 20-Tetrakis (trifluoromethyl) porphyrin, 1, was obtained by oxidative cyclization of 2-(2-trifluoro-1-hydroxyethyl) pyrrole in moderate yield. Meso-(trifluoromethyl) octaethylporphyrin, 5, was readily prepared by photochemical trifluoromethylation of octaethylporphyrin with trifluoromethyl iodide in DMF.No pertrifluoromethylation products have been detected in the present reaction. Similarly, δ-(trifluoromethyl)-octaethylchlorin, 6, and meso-(trifluoromethyl) mesoporphyrin IX dimethyl ester were obtained in moderate yields. ^1H-NMR and ^<19>F-NMR of the latter products indicated formation the four regioisomers, 9-12. These compounds showed a variety of unusual properties due to steric constrain and electronic effect of the meso-trifluoromethyl group. Both electrochemical studies and energy calculations of molecular orbitals indicated that the HOMO and LUMO of 1, 5, and 6 were markedly stabilized than those of trifluoromethyl group unsubstituted compounds. Moreover, for 5 the stabilization is much greater for the LUMO.This difference is attributable to the partial distortion of the porphyrin ring by interaction between the ethyl and trifluoromethyl groups.
|