4 Phthalocyanine and Related Analogues
91
suspension is vigorously stirred at 40–50 ºC under nitrogen until 4-nitrophthalonitrile
is completely dissolved. To the solution, 25% aqueous solution of potassium
hydroxide (75 mL) is added. After stirring at 60 ºC for 22 h, the mixture is cooled
to room temperature. The obtained polymer is washed with water, methanol, and
THF and extracted by Soxhlet extractor to provide phthalonitrile-appended polymer
(7.3 g).
Sodium (100 mg, 4.4 mmol) is dissolved in dry methanol (10 mL), and the polymer
(2.0 g) and dry THF (15 mL) is added. To the solution, ammonia gas is bubbled at
room temperature for 1 h, and then under reflux for 4 h. The mixture is cooled to room
temperature and left overnight. The resulting polymer is filtered and washed with
dry methanol, THF, methanol, and diethyl ether to provide 1,3-diiminoisoindolineappended polymer (2.0 g).
The 1,3-diiminoisoindoline-appended polymer (1.5 g) is suspended in a
mixed solvent of DMF and DMAE (1:1 (v/v)) containing 5-isopropoxy-1,3diiminoisoindoline (1.2 g). The resulting mixture is heated at 140–150 ºC and vigorously stirred under nitrogen for 20 h. After cooled to room temperature, the mixture
is poured into water (80 mL). A green solid residue is filtered, dried, and extracted
with Soxhlet extractor using dichloromethane for 18 h. Polymer-bound H 2 Pc (1.6 g)
is then obtained as a deep blue solid residue.
To the obtained polymer-bound H 2 Pc (1.6 g) suspended in dry 1,4-dioxane
(40 mL), dry HCl gas is bubbled until the concentration of HCl in the solution
becomes approximately 0.3 N. The resulting mixture is stirred for 51 h at room
temperature. The polymer residue is filtered, washed with a little amount of methanol
and diethyl ether, and extracted with Soxhlet extractor using dichloromethane until
the extract becomes colorless. After removal of the solvent from the combined solution, the fraction is purified by alumina gel column chromatography using methanol
and ethyl acetate as an eluent by changing the ratio from 15:85 to 60:40 (v/v).
A 3 B-type H 2 Pc is obtained in 24% yield (0.16 g) from the starting polymer-bound
phthalonitrile.
(3) SubPc ring-expansion method (Scheme 4.8): Kobayashi et al. revealed ringopening reactivity of SubPc in the presence of 1,3-diiminoisoindoline to provide a
A 3 B-type Pc. This method largely depends on the relative reactivities of SubPc and
1,3-diiminoisoindoline precursors. A combination of 1,3-diiminoisoindoline with
electron-donating substituents and SubPc with electron-withdrawing substituents
normally affords high selectivity of the A 3 B-type Pc and small amounts of undesired
byproducts, such as B 4 -type Pc. Practical reaction conditions are described as follows
(Musluoglu et al. 1992).
A DMSO/1-chloronaphthelene solution (2:1 (v/v)) of SubPc with an axial chlorine ligand (0.48 g, 1.1 mmol) and 15-crown-5-fused 1,3-diiminoisoindoline (2.6 g,
7.8 mmol) is heated at 80–90 ºC for 12 h. A dark green precipitate formed upon
addition of ethanol after cooled to room temperature is filtered and washed with hot
water, ethanol, and diethyl ether to provide mono-15-crown-5-fused H 2 Pc in 45%
yield (0.35 g).
91
suspension is vigorously stirred at 40–50 ºC under nitrogen until 4-nitrophthalonitrile
is completely dissolved. To the solution, 25% aqueous solution of potassium
hydroxide (75 mL) is added. After stirring at 60 ºC for 22 h, the mixture is cooled
to room temperature. The obtained polymer is washed with water, methanol, and
THF and extracted by Soxhlet extractor to provide phthalonitrile-appended polymer
(7.3 g).
Sodium (100 mg, 4.4 mmol) is dissolved in dry methanol (10 mL), and the polymer
(2.0 g) and dry THF (15 mL) is added. To the solution, ammonia gas is bubbled at
room temperature for 1 h, and then under reflux for 4 h. The mixture is cooled to room
temperature and left overnight. The resulting polymer is filtered and washed with
dry methanol, THF, methanol, and diethyl ether to provide 1,3-diiminoisoindolineappended polymer (2.0 g).
The 1,3-diiminoisoindoline-appended polymer (1.5 g) is suspended in a
mixed solvent of DMF and DMAE (1:1 (v/v)) containing 5-isopropoxy-1,3diiminoisoindoline (1.2 g). The resulting mixture is heated at 140–150 ºC and vigorously stirred under nitrogen for 20 h. After cooled to room temperature, the mixture
is poured into water (80 mL). A green solid residue is filtered, dried, and extracted
with Soxhlet extractor using dichloromethane for 18 h. Polymer-bound H 2 Pc (1.6 g)
is then obtained as a deep blue solid residue.
To the obtained polymer-bound H 2 Pc (1.6 g) suspended in dry 1,4-dioxane
(40 mL), dry HCl gas is bubbled until the concentration of HCl in the solution
becomes approximately 0.3 N. The resulting mixture is stirred for 51 h at room
temperature. The polymer residue is filtered, washed with a little amount of methanol
and diethyl ether, and extracted with Soxhlet extractor using dichloromethane until
the extract becomes colorless. After removal of the solvent from the combined solution, the fraction is purified by alumina gel column chromatography using methanol
and ethyl acetate as an eluent by changing the ratio from 15:85 to 60:40 (v/v).
A 3 B-type H 2 Pc is obtained in 24% yield (0.16 g) from the starting polymer-bound
phthalonitrile.
(3) SubPc ring-expansion method (Scheme 4.8): Kobayashi et al. revealed ringopening reactivity of SubPc in the presence of 1,3-diiminoisoindoline to provide a
A 3 B-type Pc. This method largely depends on the relative reactivities of SubPc and
1,3-diiminoisoindoline precursors. A combination of 1,3-diiminoisoindoline with
electron-donating substituents and SubPc with electron-withdrawing substituents
normally affords high selectivity of the A 3 B-type Pc and small amounts of undesired
byproducts, such as B 4 -type Pc. Practical reaction conditions are described as follows
(Musluoglu et al. 1992).
A DMSO/1-chloronaphthelene solution (2:1 (v/v)) of SubPc with an axial chlorine ligand (0.48 g, 1.1 mmol) and 15-crown-5-fused 1,3-diiminoisoindoline (2.6 g,
7.8 mmol) is heated at 80–90 ºC for 12 h. A dark green precipitate formed upon
addition of ethanol after cooled to room temperature is filtered and washed with hot
water, ethanol, and diethyl ether to provide mono-15-crown-5-fused H 2 Pc in 45%
yield (0.35 g).