Synthesis, Structure, and Chemical Property of the First Fluorine-Containing Porphycene

Abstract

[structure: see text] A pyrrolic macrocycle, beta-tetrakis(trifluoromethyl)porphycene, is the first example of a fluorine-containing porphycene. Four electron-withdrawing CF(3) substituents provide a highly distorted structure and an attractive electron-deficient nature for the porphycene framework. From the electrochemical study, it is found that the LUMO energy level for the beta-trifluoromethylporphycene is 1.24 V more stabilized compared to that for etioporphyrin. Moreover, the deprotonation of the inner N[bond]H proton in the porphycene was observed upon the addition of DBU.

Porphycenes: Facts and Prospects in Photodynamic Therapy of Cancer

“…Two main strategies (Scheme 1) have been devised to obtain the precursor 5,5'-diacyl substituted 2,2'-bipyrroles (2): acylation (Y=alkyl group) [85,123] (or formylation, Y=H) [62,66,124,125] of an adequately 4,4'-disubstituted or 3,3',4,4'-tetrasubstituted 2,2'-bipyrrole (3 or 4, respectively), in one side, or transformation of 2,2'-bypyrroles bearing two latent formyl groups to aldehydes 2 (Y=H), two ester groups in the case of 5 [126] or two 4,4,6-trimethyl-1,3-dioxan-2-yl groups in the case of 6 (G=C 7 H 13 O 2 ), on the other side [127].…”

Investigation of Aromaticity and Photophysical Properties in [18]/[20]π Porphycene Derivatives

“…Sample preparations: Etioporphycene and b-tetrakis(trifluoromethyl) [18]/ [20]p porphycenes were synthesized according to the previously reported papers [17][18][19] and dissolved in toluene (Sigma-Aldrich, spectrophotometric grade).…”

“…Chen et al [16] reported in 2007 that trifluoromethyl groups on pyrrole rings give rise to relatively air-stable [20]p porphyrin. After this work, Hayashi et al [17] also reported the successful synthesis and isolation of air-stable [20]p b-tetrakis(trifluoromethyl) porphycene ( [20]CF 3 Pc) through two-electron reduction and two protonation processes of [18]p b-tetrakis (trifluoromethyl)porphycene ([18]CF 3 Pc), which seems to be an analogue of etioporphycene ( [18]EtioPc) (Scheme 1). [18,19] Porphycene, the first porphyrin isomer, was synthesized by Vogel and co-workers in 1986, and a considerable number of research efforts have been conducted on novel synthesis, characterization, and applications of various porphycene derivatives over the past few decades.…”

Isolable Iron(II)–Porphycene Derivative Stabilized by Introduction of Trifluoromethyl Groups on the Ligand Framework

“…[2][3][4] In contrast, it is well-known that the introduction of electron-withdrawing groups at the peripheral position of the porphyrin framework stabilizes its LUMO energy level of the macrocycle. [5][6][7][8][9] Thus, it seems interesting to introduce electron-withdrawing groups at the peripheral positions of the porphycene to obtain an electron-deficient macrocycle, [10][11][12][13][14] although almost all porphycenes have only simple alkyl side chains as peripheral substituents such as methyl, ethyl, or butyl groups on the framework. [15][16][17] To further stabilize the LUMO energy level of porphycene, we have recently prepared the trifluoromethylated porphycene, 2,7,12,17-tetraethyl-3,6,13,16-tetrakis(trifluoromethyl)porphycene, Etio(CF 3 ) 4 PcH 2 .…”

“…[15][16][17] To further stabilize the LUMO energy level of porphycene, we have recently prepared the trifluoromethylated porphycene, 2,7,12,17-tetraethyl-3,6,13,16-tetrakis(trifluoromethyl)porphycene, Etio(CF 3 ) 4 PcH 2 . 10 The four electron-withdrawing trifluoromethyl substituents provided an attractive electron-deficient nature with a dramatically decreased HOMO-LUMO gap in the porphycene framework. In addition, we initially determined that its iron -oxo complex, [{Fe III Etio(CF 3 ) 4 Pc} 2 -(-O)] (1), was readily converted into a monomeric iron(III) species, [Fe III Etio(CF 3 ) 4 Pc(py) 2 ] (2-Py 2 ), via the Fe-O bond cleavage and then reduced to a iron(II) complex in pyridine solution.…”