8
S.J. MORA ET AL.
The reaction was refluxed at 200°C for 16 h under an
argon atmosphere. The solvent was removed under
high vacuum. The residue was then purified by column
chromatography on silica gel using hexanes/CH2Cl2 from
7:3 to 6:4 as eluent, to give 193 mg of 4 (84% yield)
pyrrolic NH), 1.64 (9H, s, C(CH3)3), 5.59 (2H, s, ArH),
6.45 (1H, br d, J = 5.5 Hz, ArH), 8.06 (1H, d, J = 1.9 Hz,
ArH), 8.52 (1H, d, J = 1.9 Hz, ArH), 8.62 (1H, s, CHO),
8.78 (2H, br s, pyrrolic H), 8.88 (2H, d, J = 4.3 Hz,
pyrrolic H), 8.95–8.98 (4H, m, pyrrolic H), 10.76 (1H,
s, NH), 13.65 (1H, s, OH). MALDI-TOF-MS m/z. calcd.
for C56H28F15N6O2+ 1101.203, experimental: 1101.203
(M + H)+.
1
as a purple solid. H NMR (500 MHz, CDCl3): d -2.81
(2H, s, pyrrolic NH), 1.69 (9H, s, C(CH3)3), 3.77 (3H,
s, -OMe), 7.32 (1H, t, J = 8.0 Hz, ArBIP), 7.85 (1H, d,
J = 7.6 Hz, ArBIP), 8.02–7.94 (3H, m, ArI+ArBIP), 8.14
(2H, d, J = 8.1 Hz, ArI), 8.28 (1H, d, J = 2.1 Hz, ArOH),
8.38 (1H, d, J = 2.1 Hz, ArOH), 8.84 (4H, brt, pyrrolic
H), 8.95 (2H, d, J = 4.7 Hz, pyrrolic H), 9.04 (2H, d,
J = 4.7 Hz, pyrrolic H), 10.73 (1H, s, NH), 13.98 (1H, s,
OH). MALDI-TOF-MS m/z. calcd. for C57H34F10IN6O3+
1167.157, experimental: 1167.114 (M + H)+.
5-(3-(7-(4-Methoxyphenyliminomethyl)-benzimid-
azole-2-yl)-4-hydroxy-5-tert-butylphenyl-1-yl)-10,-
15,20-tris(2,3,4,5,6-pentafluorophenyl)porphyrin,
PF15-BIP-PhOMeimine (12). A procedure similar to that
described below was previously reported [15, 27]. A
solution of 11 (22 mg, 0.020 mmol) and p-anisidine
(2.5 mg, 0.020 mmol) with 4Å molecular sieves in
2 mL of dry CH2Cl2 was stirred and kept under an
argon atmosphere at room temperature. After 15 min,
pyrrolidine (0.002 mmol) was added. After 24 h, the
reaction mixture was filtered and the molecular sieves
washed several times with dry CH2Cl2. The solvent was
removed under reduced pressure to afford 20 mg of pure
5-(3-(7-Hydroxymethylbenzimidazole-2-yl)-4-hyd-
roxy-5-tert-butylphenyl-1-yl)-10,15,20-tris(2,3,4,5,6-
pentafluorophenyl)porphyrin, PF15-BIPCH2OH (10).
Compound 8 (73.4 mg, 0.0649 mmol) in 4 mL of dry
CH2Cl2 was stirred at -78°C under argon. A solution of
25% DIBALH (260 mL, 0.3892 mmol) in toluene was
added dropwise and the reaction was stirred for 4 h. To
quench the reaction, 8 mL of 3M HCl solution (kept
cold) was added and the mixture was stirred overnight.
The resulting mixture was extracted 3 times with CH2Cl2,
controlling the pH of the aqueous phase at around 7 using
a sodium bicarbonate (NaHCO3) solution. The organic
layer was then dried over Na2SO4 and the solvent was
removed under reduced pressure. The solid was purified
by column chromatography on silica gel using a gradient
of hexanes/CH2Cl2 1:1 to CH2Cl2 as the eluent, to give
183 mg of 10 (70% yield). 1H NMR (500 MHz, CDCl3):
d -2.88 (2H, s, pyrrolic NH), 1.68 (9H, s, C(CH3)3), 4.80
(2H, s, CH2), 6.73 (1H, d, J = 6.6 Hz, ArH), 6.91 (1H,
t, J = 7.6 Hz, ArH), 7.42 (1H, d, J = 8.1 Hz, ArH), 8.21
(1H, d, J = 2.0 Hz, ArH), 8.32 (1H, d, J = 2.1 Hz, ArH),
8.84 (2H, d, J = 4.2 Hz, pyrrolic H), 8.88–8.92 (4H, m,
pyrrolic H), 9.04 (2H, d, J = 4.5 Hz, pyrrolic H), 10.16
(1H, s, NH), 14.20 (1H, s, ArOH); isomeric species were
detected in the spectrum. MALDI-TOF-MS m/z. calcd.
for C56H30F15N6O2+ 1103.218, experimental: 1103.224
(M + H)+.
5-(3-(7-Formylbenzimidazole-2-yl)-4-hydroxy-5-
tert-butylphenyl-1-yl)-10,15,20-tris(2,3,4,5,6-pentafluo-
rophenyl)porphyrin, PF15-BIPCHO (11). A procedure
similar to that described below was previously reported
[15]. Compound 10 (30.1 mg, 0.027 mmol) was dissolved
in 15 mL of dry CH2Cl2, and the solution was stirred under
argon. Activated MnO2 was added carefully at room
temperature, and the oxidation reaction was followed by
thin-layer chromatography (TLC). After completion, the
reaction mixture was filtered through a pad of celite and
the residue was washed with CH2Cl2. The solvent was
removed under reduced pressure. The solid was purified
by column chromatography on silica gel using hexanes/
CH2Cl2 3:2 as the eluent to afford 21.9 mg of pure 11
(74% yield). 1H NMR (500 MHz, CDCl3): d -3.26 (2H, s,
1
12 (83% yield). H NMR (500 MHz, CDCl3): d -2.81
(2H, s, pyrrolic NH), 1.69 (9H, s, C(CH3)3), 3.41 (3H,
s, OCH3), 6.38–6.42 (2H, m, ArH), 6.80–6.84 (2H, m,
ArH), 7.35 (overlap with solvent, br s, ArH), 7.85 (1H, br
s, ArH), 8.26 (1H, d, J = 2.0 Hz, ArH), 8.33 (1H, d, J =
2.1 Hz, ArH), 8.53 (1H, br s, CH=N), 8.84 (2H, d, J = 4.5
Hz, pyrrolic H), 8.87–8.90 (4H, m, pyrrolic H), 9.09 (2H,
d, J = 4.6 Hz, pyrrolic H), 11.73 (1H, s, NH), 14.20 (1H,
s, OH). MALDI-TOF-MS m/z. calcd. for C63H35F15N7O2+
1206.260, experimental: 1206.205 (M + H)+.
5-((7-N-Cyclohexyliminebenzimidazole-2-yl)-4-
hydroxy-5-tert-butylphenyl-1-yl)-10,15,20-tris(2,3,-
4,5,6-pentafluorophenyl)porphyrin, PF15-BIP-Cyimine
(13). This reaction uses the same conditions as the
previous reaction but employs cyclohexylamine. The
solvent was removed under reduced pressure to afford
25 mg of the desired pure compound 13 (87% yield). 1H
NMR (500 MHz, CDCl3): d -2.75 (2H, s, pyrrolic NH),
0.87–0.95 (3H, m, cy ring), 1.05–1.12 (2H, m, cy ring),
1.26–1.32 (3H, m, cy ring), 1.43–1.46 (2H, m, cy ring),
1.71 (9H, s, C(CH3)3), 3.09–3.14 (1H, m, CH-N), 7.38
(2H, d, J = 4.2 Hz, ArH), 7.88–7.91 (1H, m, ArH), 8.28
(1H, d, J = 2.0 Hz, ArH), 8.33 (1H, d, J = 2.1 Hz, ArH),
8.42 (1H, s, CH=N), 8.87 (2H, d, J = 4.5 Hz, pyrrolic
H), 8.89–8.92 (4H, m, pyrrolic H), 9.17 (2H, d, J =
4.6 Hz, pyrrolic H), 11.92 (1H, br s, NH), 14.22 (1H,
s, OH). 19F NMR (470 MHz, CDCl3): d -161.80 (Fmeta
td), -161.66– -161.49 (Fmeta, m), -151.84– -151.66 (Fpara
,
,
m), -136.92– -136.47 (Fortho, m). MALDI-TOF-MS
m/z. calcd. for C62H39F15N7O+ 1182.297, experimental:
1182.205 (M + H)+.
5-(3-(7-Hydroxymethylbenzimidazole-2-yl)-4-hydroxy-5-
tert-butylphenyl-1-yl)-15-(4-iodophenyl)-10,20-bis(2,3,4,-
5,6-pentafluorophenyl)porphyrin, PF10-pI-BIPCH2OH
(14). A solution of compound 9 (75 mg, 65 mmol)
in 5 mL of dry CH2Cl2 was stirred at -78°C under an
Copyright © 2019 World Scientific Publishing Company
J. Porphyrins Phthalocyanines 2019; 23: 8–10