MnIII(Porphyrin)-Based Porous Coordination Polymers: Synthesis, Catalytic Activities…
solution was filtered, and the solvent was evaporated. The
dried product was then chromatographed on a silica gel
column by using CH2Cl2 as the eluting solvent to remove
unreacted Mn(C2H3O2)2. Afterwards, Mn(F5CPp)(OAc)
was afforded by alkaline hydrolysis of the Mn(F5
EPp)(OAc). The spectral characterization of the synthe-
sized metalloporphyrins as follows:
1722, 1609, 1434, 1278, 1107, 961, 802. 1H NMR
(400 MHz, CDCl3): d (ppm) = 8.92–8.83 (d, J = 19.0, 8H,
Pyrrole–H), 8.48–8.29 (m, 8H, Ar–H), 1.57–1.43 (m, 6H,
–CH3), -2.80 (d, J = 19.8 Hz, 2H, N–H).
Mn(F10CPp)(OAc) was prepared following the proce-
dures described for Mn(F5CPp)(OAc) except that
H2(F10EPp) was used instead of H2(F5EPp). Yield: 96 %;
M.p.: [250 °C. Elemental analysis Calcd. for C48H21
MnF10N4O5: C, 58.91; H, 2.16; N, 5.72; Found: C, 58.75;
H, 1.92; N, 5.55; GC–MS observed and calculated
Mn(F5CPp)(OAc): yield: 85 %; M.p.: [250 °C. Ele-
mental analysis Calcd. for C49H26MnF5N4O8: C, 63.45; H,
2.61; N, 6.21; Found: C, 63.41; H, 2.69; N, 6.30; GC–MS
observed and calculated [Mn(F5CPp)]?: 889.1 amu; UV–
Vis (nm, DMF) kmax: 475 (Soret band), 575, 610; FT-IR
(cm-1): 3411, 2922, 1703, 1601, 1488, 1228, 1108, 972,
783.
[Mn(F10CPp)]?: 935.1 amu; UV–Vis (nm, DMF) kmax
:
473 (Soret band), 568, 599; FT-IR (cm-1): 3434, 2919,
1704, 1609, 1499, 1272, 1119, 980, 805.
2.4 Synthesis of MnIII(F5CPp)–MII
and MnIII(F10CPp)–MII (M = Mn, Co, Ni; CP1–
CP6)
2.3 Synthesis of H2(F10EPp) and Mn(F10CPp)(OAc)
Distilled pyrrole (30 mL, 434 mmol) was added in a three-
necked flask, stirring at room temperature under a nitrogen
atmosphere, then methyl 4-formylbenzoate (1.64 g,
10 mmol) was added dropwise. 15 min later, 2–3 drops of
boron trifluoride etherate was added, the color of solution
turn to yellow-green. After 25 min, 20 mL CH2Cl2 and
10–15 drops saturated NaOH aqueous solution were added
successively, the pH of solution was about 8. And then,
added anhydrous sodium sulfate to remove water. Standing
15 min, dump out the supernatant, the CH2Cl2 and pyrrole
were evaporated respectively, and the orange oily mixture
was obtained. The mixture was then passed through a silica
gel column by using CH2Cl2 as the eluting solvent. The first
pale yellow band was collected, then evaporated most of
solvent, the yellow oily residual was obtained. A small
amount of anhydrous ethanol was added in the yellow oily
residual, then placed in the refrigerator, overnight, there
was pale yellow precipitate present, and was identified as
the 5-methyl benzoate-dipyrromethane. Yield: 49.6 %;
M.p.: 131 °C. Elemental analysis Calcd. for C17H16N2O2: C
72.84; H, 5.75; N, 9.99; Found: C, 72.82; H, 5.68; N, 9.86.
Pentafluorobenzaldehyde (1.96 g, 10 mmol) dissolved in
hot propionic acid (70 mL), and the propionic acid solution
(10 mL) of 5-methyl benzoate-dipyrromethane (2.80 g,
10 mmol) was added dropwise. The solution was refluxed
for 1 h. After cooling to room temperature, most of propionic
acid was evaporated and 30 mL ethanol was added. Then the
mixture was cooled for 10 h in refrigerator and filtrated
under vacuum. The further purified by column chromatog-
raphy (silica, CH2Cl2), and a desired purple solid of com-
pound H2(F10EPp) was obtained. Yield: 6.8 %; M.p.:
[250 °C; Elemental analysis Calcd. for C48H24F10N4O4: C,
63.30; H, 2.66; N, 6.15; Found: C, 63.25 H, 2.58 N, 6.32;
GC–MS observed [M ? H]?: 911.2 amu, calculated M:
910.2 amu; UV–Vis (nm, CH2Cl2) kmax: 415 (Soret band),
511, 553, 593, 652 (Q bands); FT-IR (cm-1): 3317, 2947,
A mixture of Mn(F5CPp)(OAc) (0.009 g, 0.01 mmol),
Mn(OAc)2Á4H2O (0.007 g, 0.03 mmol), and DMF (4 mL),
was stirred, and then sealed in a 10 mL Teflon-lined
stainless steel reactor, kept under autogenous pressure at
90 °C for 72 h. The dark-purple precipitate of reaction was
filtered and washed with water, CH2Cl2, DMF and ethanol
to remove any unreacted monomer. The target product
Mn(F5CPp)–Mn (CP1) was dried at 110 °C under vacuum
for 24 h. CP2 and CP3 were prepared following the pro-
cedure described for CP1 except that Co(OAc)2Á4H2O
(0.007 g, 0.03 mmol) and Ni(OAc)2Á4H2O (0.007 g,
0.03 mmol) were used instead of Mn(OAc)2Á4H2O.
CP4–CP6 were prepared following the procedures
described for CP1–CP3 except that Mn(F10CPp)(OAc)
(0.010 g, 0.01 mmol) was used instead of Mn(F5CPp)(OAc).
2.5 Oxidation Procedure and Catalysts Reuse
All the oxidation reactions were carried out in asealed vial. A
mixture of ethylbenzene (0.1 mmol), TBHP (0.4 mmol), and
the catalyst (CP1–CP6, 5 mg) in acetonitrile (1 mL) was
stirred at 65 °C for 12 h. When time up, the results of reac-
tion were examined by GC. 1H NMR and MS spectral data
confirmed the identities of the product. The catalyst was
recovered by centrifugation, washed with water, methanol,
acetonitrile and diethyl ether successively, and dried in
vacuum at 110 °C to remove the solvent for several hours
before new utilization under similar reaction conditions.
After the use of catalyst for three consecutive times, the
acetophenone yield was no significant decline and the
selectivity remained over 99 %. The leaching experiments
were made in the same conditions described above, after
12 h of reaction the catalyst was isolated by centrifugation
and no characteristic spectrum of the metalloporphyrin was
detectable in the supernatant by UV–Vis.
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