Tris corrole

Octaethyl and tris(pentafluorophenyl) corroles, known as oec and tpfc, respectively, are also efficient for the stabilization of P(VI) phosphorus [53,54]. The electron-rich oec reacts with PCI3 to form (oec)P=0 40 that can be further derived into dihydrido 41a, dimethyl 41b and diphenyl 41c compounds by reduction with LiAlH4 and reactions with methyl and phenyl Grignard reagents. 

In the tris-pentafluorophenyl analog (TFPC), in contrast to other Co corroles, aromatic amines can substitute PPh3 to form six-coordinate trivalent bis(amine) complexes.788 Bis-chlorosulfon-ation of TFPC occurs regioselectively to give the 2,17-(pyrrole)-bis-chlorosulfonated derivative fully characterized as its triphenylphosphinecobalt(III) complex.789 The amphiphilic bis-sulfonic acid was also obtained. 

R. S. Czemuszewicz, V. Mody, A. Czader, M. Galezowski, and D. T. Gryko, Why the chromyl bond is stronger than the perchromy bond in high-valent oxochromium(IV, V) complexes of tris(pentafluor-ophenyl)corrole,/. Am. Chem. Soc., 131 (2009) 14214-14215. 

Two papers have been published to date on meso-substituted derivatives of corrole [30, 31]. Four new cobalt complexes have been prepared and characterized [triphenylphosphine(2,3,7,8,12,13,17,18-octamethyl-1O-phenyl-corrolato)-cobalt (III)] (Co(OMMPC)PPh3), [triphenylphosphine (2,3,7,8,12,13,17,18-octamethyl-5,10,15-triphenylcorrolato)cobalt (III)] (Co(OMTPC)PPh3), [tri-phenylphosphine(2,3,7,8,12,13,17,18-octamethyl-5,10-diphenylcorrolato)cobalt (III)] (Co(5,10-OMDPC)PPh3) and [triphenylphosphine (2,3,7,8,12,13,17,18-octamethyl-5,15-diphenylcorrolato)cobalt(III)] (Co(5,15-OMDPC)PPh3). 

Osuka and Hori (10EJOC2379) have reported the synthesis of ABC-type corroles 18 (Scheme 10) by nucleophilic substitution of meso-5,10,15-tris... 

In 2006 (06TL8171), 2,3 -linked 31 and 3,3 -linked 32 3, 3 -corrole dimers (Scheme 15) have been achieved by heating a 1,2,4-trichlorobenzene solution of 5,10,15-tris(pentafluorophenyl)corrole 8 (Ar=C6F5) at 200°C. In one... 

One example of a synthetic approach to free-base corroles is known that does not involve the cyclization of dideoxybiladienes-ac and related species. This involves the acid catalyzed 2 + 2 condensation between the bis(formylpyrrolyl) sulfide 2.26 and the diacid dipyrrylmethane species 2.36. This afforded the weio-thiaphlorin macrocycle 2.101 in 52% yield (Scheme 2.1.22). Heating this product at reflux in o-dichlorobenzene effects sulfur extrusion and generates corrole 2.102 in 35-40% yield. Interestingly, when the extrusion process is performed in the presence of tri-phenylphosphine (PPh3), the yield of corrole increases to 60%. However, a mechanistic rationale for this latter interesting finding has yet to be put forth. 

To date, four synthetic approaches have been used to produce tris-(me5o-phenyl)cobalt(III) corroles successfully. Three of these were reported by Paolesse, et al. in 1993 and are shown in Scheme 2.1.40. Of these, one involved as its first step the POCls-catalyzed reaction between the 2-benzoylpyrrole-5-carboxylic acid 2.152 and the phenyl-substituted dipyrrylmethane 2.144. The resulting biladiene-ac was then treated without isolation with Co(OAc)2 and PPh3 to give the desired cobalt(III) corrole 2.153 in 2% yield. ... 

The tedious preparation of the monopyrrolic precursor 2.147 necessary for the tris-(phenyl)cobalt(III) corrole 2.153 led Paolesse, et al. to consider a third approach to preparing tris-(phenyl)cobalt(III) corroles. It centers around an initial acid-catalyzed condensation between the diacid dipyrrylmethane 2.144 with benzaldehyde (2.154) that is followed by a subsequent cyclization step carried out in the presence of Co(OAc)2 and PPh3. In this case, it was found that 2,3-dichloro-5,6-dicyano-I,4-benzoquinone (DDQ) helped mediate the requisite final oxidation step. While this approach did give a slightly lower yield of corrole (18%), it had the advantage of being quite streamlined. 

It is perhaps not surprising that metallocorroles may be prepared from preformed metal-free corroles as well as from linear pyrrolic precursors. In fact, the former metal insertion approach has allowed a considerable number of metallocorroles to be prepared, including complexes containing mono-, di-, tri-, and tetravalent metal cations (as discussed above in Sections 2.1.2.1.1-2.1.2.1.3). The following section will describe examples of the latter approach to metallocorroles, that is, via insertion of a metal center into a pre-formed corrole ring. 

Attempts to insert cobalt(II) into A(21)-methyl corrole 2.196 have also been made. In 1971, for instance, Johnson, et al. tried treating corrole 2.196 with Co(C104)2 6EtOH in the presence of pyridine. However, only the demethylated cobalt(III) corrole(Py) species 2.125a was obtained (Scheme 2.1.80). ... 

Bendix J, Dmochowski U, Gray HB, Mahammed A, Simkhovich L, Gross Z (2000) Structural, electrochemical, and photophysical properties of gallium(III) 5,10,15-tris (pentafluorophenyl)corrole. Angew Chem Int Ed 39 4048-4051... 

Meier-Callahan AE, Gray HB, Gross Z (2000) Stabilization of high-valent metals by corroles oxo[tris(pentafluorophenyl)corrolato]chromium(V). Inorg Chem 39 3605-3607... 

Simkhovich L, Galili N, Saltsman I, Goldberg I, Gross Z (2000) Coordination chemistry of the novel 5,10,15-tris(pentafluorophenyl)corrole synthesis, spectroscopy, and structural characterization of its cobalt(III), rhodium(III), and iron(IV) complexes. Inorg Chem 39 2704-2705... 

Mahammed A, Goldberg I, Gross Z (2001) Highly selective chlorosulfonation of tris (pentafluorophenyl)corrole as a synthetic tool for the preparation of amphiphilic corroles and metal complexes of planar chirality. Org Lett 3 3443-3446... 

Simkhovich L, Mahammed A, Goldberg I, Gross Z (2001) Synthesis and characterization of germanium, tin, phosphorous, iron and rhodium complexes of tris(pentafluorophenyl)corrole, and the utilization of the iron and rhodium corroles as cyclopropanation catalysts. Chem Eur J 7 1041-1055... 

Capar C, Hansen LK, Conradie J, Ghosh A (2010) P-octabromo-me.s0-tris(pentafluoro-phenyl)corrole reductive demetalation-based synthesis of a heretofore inaccessible, perhalo-genated free-base corrole. J Porphyr Phthalocyanines 14 509-512... 

Collman and Decreau have developed a modified solvent-free approach for preparation of new free base tris-aryl and tris-pyrimidyl corroles using MW irradiation [186]. Compared with conventional heating, the MW technique afforded higher yields and led to noticeably cleaner reaction products (Scheme 8.74). 

It has been reported that the macrocycle known as Corrole is an effective catalyst toward CO2 reduction , (5.16). The Co (II) corrole [PhsPCo (tpfc)] (tpfc = 5, 10, 15-tris(pentafluorophenyl) corrole) exhibit catalytic activity in ACN. Stepwise reduction to the [Co (tpfc)] and [Co (tpfc)] states was... 

Figure 10.12 2,17-Bis-sulfonato-5,10,15-tri(pentafluorophenyl)corrole manganese complex 14 [59,60], tetrakis(sulfonato) phthalocyanin copper complex 15 [61], and meso-tetrakis (p-carboxyphenyl)-porphyrln manganese complex 16 [62].

Photoreaction of isoquinolinone in solid neat conditions afforded many kinds of [4 + 4] cyclodimers, however in the presence of 1,3-benzenediol as a host molecule, a single isomer was obtained. Irradiation of 5,10, 15-tris(pentafluorophenyl)corrole (274) slowly gave the 3,3 -corrole dimer (275) and the 3,3, 17, 3"-corrole trimer (276). ... 

In 2006, Abu-Omar reported on stop-flow studies of the reactions of the soluble ArlNTs reagent ( Ar=ort/i )- BuS02C6H4), an analogue of the soluble iodosylarene described above, with the manganese corrole complex [(tpfc)Mn (EtOAc)] (tpfc=5,10,15-tris(pentafluorophenyl)corrole (Scheme 19) [82]. [(tpfc) Mn(EtOAc)] can catalyze the reaction of PhINTs with styrene to form aziridines. In this study, an initial adduct of the ArlNTs with Mn corrole leads to a detectable mono-adduct [(tpfc)Mn N(Ts)FAr ] (Scheme 16). The initially formed adduct then loses ArI to form an isolable Mn imino complex [(tpfc)Mn(=NTs)]. This imino complex, however, is not the active catalyst for imino transfer to olefins. 

The oxidation rates of a series of alkenes by various Mn(V)-oxo corrole complexes (corrole = 5,10,15-tris(pentafiuorophenyl) 5,15-bis(pentafluorophenyl)-10-(phenyl) 5,15-bis(phenyl)-10-(pentafluorophenyl) and 5,10,15-tris(phenyl)corroles) in different solvents indicated that the oxygen atom transfer pathway between Mn(V)-oxo corrole and alkene is solvent dependent. ... 

Metalloporphyrins and metallocorroles have been shown to acts as alkene aziridina-tion catalysts, and the extent of macrocycle halogenation has been shown to correlate with catalyst performance. Mn(III) complexes of 5,10,15-Tris(pentafluorophenyl) corrole are active in aziridination catalysis [101, 102] electron-withdrawing substituents on the corrole are required to facilitate amide transfer to the alkene. Fluorination of corroles also leads to stable metal imide intermediates during aziridination reactions. 

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