SYNTHESIS OF MESO-TETRAARYLPORPHYRINS POSSESSING AMINO AND CARBOXY GROUPS
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residue was purified with FCC, giving di-protected com-
5-[3-Hydroxy-5-(ethoxycarbonylmethoxy)phenyl]-
10,15,20-tris(3,5-di-tert-butylphenyl)porphyrin. To a
solution of the above silyl ether (100 mg, 76 µmol) in
THF (20 mL) was added tetrabutylammonium fluoride
(TBAF, 240 mg, 0.38 mmol) in a small amount of THF.
After being stirred at room temperature for 1.5 h, the
reaction mixture was neutralized by aq. 4% NaHCO3 and
extracted with CHCl3. The organic phase was washed
twice with water, dried over Na2SO4 and concentrated
in vacuo. The residue was purified with FCC (0–1%
Et2O-CH2Cl2) to give the titled compound (64.8 mg,
pound (42.0 mg, 29 µmol, 29%) as the first eluate (2:1
petroleum ether-CH2Cl2) and mono-protected compound
(32.7 mg, 27 µmol, 27%) as the second eluate (1:2 petro-
leum ether-CH2Cl2). 5-(3-tert-butyldiphenylsilyloxy-5-
hydroxyphenyl)-10,15,20-tris(3,5-di-tert-butylphenyl)-
porphyrin (mono-protected). 1H NMR (CDCl3): δ, ppm
8.88 (4H, s, 12-, 13-, 17-, 18-H), 8.80 (2H, d, J = 5 Hz, 2-,
8-H), 8.67 (2H, d, J = 5 Hz, 3-, 7-H) 8.08–8.02 (6H, m,
2-, 6-H of 10,15,20-phenyl), 7.85–7.82, 7.42–7.36
(4H + 6H, m, Si(C6H5)2), 7.81, 7.78 (2H + 1H, m, 4-H
of 10,15,20-phenyl), 7.29, 7.19, 6.74 (each 1H, m, 2-, 4-,
6-H of 5-phenyl), 4.94 (1H, br-s, 5-OH of 5-phenyl), 1.55,
1.53, 1.52, 1.51 (18H + 18H + 9H + 9H, s, 3-, 5-C(CH3)3
of 10,15,20-phenyl), 1.15 (9H, s, SiC(CH3)3), -2.81 (2H,
s, pyrrole-NH × 2). MS (TOF): m/z found 1221.75,
calcd. for C84H96N4O2Si: [M]+, 1221.73. 5-[3,5-bis(tert-
butyldiphenylsilyloxy)phenyl]-10,15,20-tris(3,5-di-
tert-butylphenyl)porphyrin (diprotected). 1H NMR
(CDCl3): δ, ppm 8.85 (4H, s, 12-, 13-, 17-, 18-H), 8.70
(2H, d, J = 4 Hz, 2-, 8-H), 8.37 (2H, d, J = 4 Hz, 3-, 7-H),
8.05 (4H, d, J = 2 Hz, 2-, 6-H of 10,20-phenyl), 8.04 (2H,
d, J = 2 Hz, 2-, 6-H of 15-phenyl), 7.80 (2H, br-s, 4-H of
10,20-phenyl), 7.75 (1H, br-s, 4-H of 15-phenyl), 7.66
(8H, d, J = 7 Hz, 2-, 6-H of Si-phenyl × 4), 7.36 (4H, t,
J = 7 Hz, 4-H of Si-phenyl × 4), 7.30 (8H, dd, J = 7, 7
Hz, 3-, 5-H of Si-phenyl × 4), 7.16 (2H, d, J = 2 Hz, 2-,
6-H of 5-phenyl), 6.71 (1H, t, J = 2 Hz, 4-H of 5-phenyl),
1.54 (36H, s, 3-, 5-C(CH3)3 of 10,20-phenyl), 1.49 (18H,
s, 3-, 5-C(CH3)3 of 15-phenyl), 1.05 (18H, s, SiC(CH3)3 ×
2), -2.90 (2H, s, pyrrole-NH × 2). MS (TOF): m/z found
1459.86, calcd. for C100H114N4O2Si2: [M]+, 1459.85.
5-[3-tert-Butyldiphenylsilyloxy-5-(ethoxycarbonyl-
methoxy)phenyl]-10,15,20-tris(3,5-di-tert-butyl-
phenyl)porphyrin. Potassium carbonate (150 mg, 1.1
mmol) was added to a solution of the above mono-silyl-
protected phenolic compound (200.4 mg, 0.16 mmol) in
acetone (20 mL) and the mixture was stirred for 5 min,
then ethyl bromoacetate (180 µL, 1.6 mmol) was added.
After being stirred at room temperature overnight, the
reaction mixture was diluted with water and extracted
with CHCl3. The organic phase was washed twice with
water, dried over Na2SO4 and concentrated in vacuo. The
residue was purified with FCC (2:1 hexane-CH2Cl2) to
give the titled compound (181.1 mg, 0.14 mmol, 86%). 1H
NMR (CDCl3): δ, ppm 8.88 (4H, s, 12-, 13-, 17-, 18-H),
8.78 (2H, d, J = 5 Hz, 2-, 8-H), 8.62 (2H, d, J = 5 Hz,
3-, 7-H), 8.12–8.03 (6H, m, 2-, 6-H of 10,15,20-phenyl),
7.85–7.81, 7.44–7.35 (4H + 6H, m, Si(C6H5)2), 7.80 (2H,
m, 4-H of 10,20-phenyl), 7.78 (1H, m, 4-H of 15-phenyl),
7.33, 7.26, 6.85 (each 1H, m, 2-, 4-, 6-H of 5-phenyl),
4.59 (2H, s, OCH2CO), 4.19 (2H, q, J = 7 Hz, COOCH2),
1.55, 1.53, 1.515, 1.506 (18H + 18H + 9H + 9H, s, 3-,
5-C(CH3)3 of 10,15,20-phenyl), 1.20 (3H, t, J = 7 Hz,
COOCCH3), 1.16 (9H, s, SiC(CH3)3), -2.82 (2H, s, pyr-
role-NH × 2). MS (TOF): m/z found 1307.74, calcd. for
C88H102N4O4Si: [M]+, 1307.77.
1
61 µmol, 79%). H NMR (CDCl3): δ, ppm 8.98–8.88
(8H, m, 2-, 3-, 7-, 8-, 12-, 13-, 17-, 18-H), 8.14–8.08
(6H, m, 2-, 6-H of 10,15,20-phenyl), 7.83–7.79 (3H, m,
4-H of 10,15,20-phenyl), 7.36, 7.34, 6.82 (each 1H, m,
2-, 4-, 6-H of 5-phenyl), 4.77 (2H, s, OCH2CO), 4.26
(2H, q, J = 7 Hz, COOCH2), 1.55, 1.54 (18H + 36H, s,
3-, 5-C(CH3)3 of 10,15,20-phenyl), 1.23 (3H, t, J = 7 Hz,
COOCCH3), -2.72 (2H, s, pyrrole-NH × 2). MS (TOF):
m/z 1069.60, calcd. for C72H85N4O4: [MH]+, 1069.66.
5-{3-[2-(Tert-Butoxycarbonylamino)ethoxy]-5-
(ethoxycarbonylmethoxy)phenyl}-10,15,20-tris(3,5-di-
tert-butylphenyl)porphyrin (Boc-P1-OEt). Potassium
carbonate (140 mg, 1.0 mmol) was added to a solution
of the above phenolic compound (79.4 mg, 61 µmol) in
DMF (20 mL) and the mixture was stirred for 5 min, then
commercially available 1-(tert-butoxycarbonylamino)-2-
bromoethane (67.0 mg, 0.30 mmol) in a small amount
of DMF was added dropwise at room temperature. After
being stirred at 70 °C overnight, the reaction mixture
was diluted with water and extracted with CHCl3. The
organic phase was washed three times with water, dried
over Na2SO4 and concentrated in vacuo. The residue was
purified with FCC (1–2% Et2O-CH2Cl2) and recrystalli-
zation (MeOH) to give Boc-P1-OEt (49.2 mg, 41 µmol,
1
67%). H NMR (CDCl3): δ, ppm 9.01–8.78 (8H, m, 2-,
3-, 7-, 8-, 12-, 13-, 17-, 18-H), 8.09–8.05 (6H, m, 2-, 6-H
of 10,15,20-phenyl), 7.79 (2H, t, J = 2 Hz, 4-H of 10,20-
phenyl), 7.78 (1H, t, J = 2 Hz, 4-H of 15-phenyl), 7.45,
7.39, 6.93 (each 1H, m, 2-, 4-, 6-H of 5-phenyl), 5.07
(1H, m, CONH), 4.77 (2H, s, OCH2CO), 4.25 (2H, q,
J = 7 Hz, COOCH2), 4.19 (2H, m, OCH2CN), 3.60 (2H,
m, OCCH2N), 1.524, 1.517, 1.51 (36H + 9H + 9H, s, 3-,
5-C(CH3)3 of 10,15,20-phenyl), 1.44 (9H, s, C(CH3)3 of
Boc), 1.23 (3H, t, J = 7 Hz, COOCCH3), -2.74 (2H, s,
pyrrole-NH × 2). MS (TOF): m/z found 1212.82, calcd.
for C79H98N5O6: [MH]+, 1212.75.
5-{3-[2-(tert-Butoxycarbonylamino)ethoxy]-5-
(carboxymethoxy)phenyl}-10,15,20-tris(3,5-di-tert-
butylphenyl)porphyrin (Boc-P1-OH). Boc-P1-OEt
(26.7 mg, 22 µmol) was dissolved in aq. 2 N NaOH
(10 mL) and THF (10 mL). After being stirred at room
temperature for 1.5 h, the reaction mixture was diluted
with water, neutralized with aq. 2% HCl and extracted
with CHCl3. The organic phase was washed twice with
water, dried over Na2SO4 and concentrated in vacuo. The
residue was purified with FCC (10% MeOH-CH2Cl2) to
Copyright © 2010 World Scientific Publishing Company
J. Porphyrins Phthalocyanines 2010; 14: 379–388