Supporting information
Gelation Properties of Poly(aryl ether) dendrons bearing long alkyl chains
Tomoaki Ando and Kazuaki Ito*
Department of Chemistry and Chemical Engineering, Graduate School of Science and
Engineering, Yamagata University, Jhonan 4-3-16, Yonezawa, 992-8510 JAPAN
Synthesis of methyl 3,4,5-trihydroxy benzoate (3). [1]
A mixture of 3,4,5-trihydroxy benzoic acid (10.0 g, 58.8 mmol), conc sulfuric acid (4.61 g,
47.1 mmol) and dry methanol (87 ml) was heated at 60 C for 24 h. After cooling to r.t.,
removal of solvent gave solid residue, which was dissolved with ethyl acetate. The
solution was washed with water several times and the organic layer was dried over
anhydrous sodium sulfate. Removal of solvent gave 3 (6.40 g, 64 % yield) as white
crystals.
3: 78% yield, white crystals. mp 120-124 C.
1H-NMR
(DMSO-d6): 3.71(s, CO2CH3, 3H), 6.90(s, Ar-H, 2H), 10.0 (bs, OH, 3H).
.
Synthesis of methyl 3,4,5-tris(n-alkyl-1-yloxy) benzoate (1a8 and 1a12). [2]
To a mixture of methyl 3,4,5-trimethoxy benzoate (3) (5.00 g, 27.2 mmol), potassium
carbonate (22.5 g, 163 mmol) and DMF (133 ml) was added 1-bromooctane (21.0 g, 109
mmol) over 5 min under nitrogen atmosphere. After the addition was completed, the
mixture was heated at 60 C for 12 h. After cooling to r. t., the reaction mixture was
poured into the ice-water and then extracted with chloroform. The organic layer was
separated and dried over anhydrous sodium sulfate. Removal of the solvent gave oily
residue,
which
was
subjected
column
chromatography
on
alumina
using
dichloromethane as an eluent to give colorless oil. The oil was further subjected to
column chromatography on silica gel using hexane / ethyl acetate (10/1, v/v) as an
eluent to give 1a8 (11.3 g, 80 % yield) as oil. The analogous compound (1a12) was
obtained the similar reaction procedure by using 1-buromododecane as a starting
material instead of 1-bromooctane.
1a8: 80 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 7.2 Hz, 9H), 1.20-1.38 (bs, CH2 x
12, 24H), 1.46 (m, CH2 x 3, 6H), 1.73 (quintet, CH2, J = 8.0 Hz, 2H), 1.80(quintet, CH2 x
2, 4H, J = 7.6 Hz), 3.88(s, CO2CH3, 3H), 4.00(t, CH2OAr x 3, J = 6.8Hz, 6H),7.24,(s, Ar-H,
2H).
1a12: 84 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 7.2 Hz, 9H), 1.20-1.38 (bs,CH2 x
24, 48H), 1.46 (m, CH2 x 3, 6H), 1.73 (quintet, CH2, J = 8.0 Hz, 2H), 1.80 (quintet, CH2 x
2, 4H, J = 7.6 Hz), 3.88 (s, CO2CH3, 3H), 4.00(t, CH2OAr x 3, J = 6.8Hz, 6H),7.24,(s, Ar-H,
2H).
Synthesis of 3,4,5-tris(n-alkyl-1-yloxy) benzoate (1b8 and 1b12). [3]
A mixture of 1a8 (1.5g、2.88mmol) and potassium hydroxide (1.13g, 20.2mmol) in
ethanol (15ml) was refluxed for 3 . After cooling to room temperature, the reaction
mixture was acidified by 10% HCl aqueous solution in an ice-bath. The precipitate was
collected by filtration and then dried in vacuo. 1b8 was obtained in 80 % yield (1.17 g) as
white crystals. The analogous compound (1b12) was obtained the similar reaction
procedure by using 1a12 as a starting material instead of 1a8.
1b8: 80 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 7.2 Hz, 9H), 1.20-1.38 (bs, CH2 x
12, 24H), 1.46 (m, CH2 x 3, 6H), 1.73 (quintet, CH2, J = 7.6 Hz, 2H), 1.80 (quintet, CH2 x
2, 4H, J = 7.6 Hz), 4.01 (t, CH2OAr x 2, J = 6.4 Hz, 4H), 4.03 (t, CH2OAr, J = 6.4 Hz, 2H),
7.24,(s, Ar-H, 2H).
1b12: 71 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 7.2 Hz, 9H), 1.20-1.38 (bs,CH2 x
24, 48H), 1.46 (m, CH2 x 3, 6H), 1.73 (quintet, CH2, J = 7.6 Hz, 2H), 1.80 (quintet, CH2 x
2, 4H, J = 7.6 Hz), 3.88 (s, CO2CH3, 3H), 4.01 (t, CH2OAr x 2, J = 6.4 Hz, 4H) , 4.03 (t,
CH2OAr, J = 6.6 Hz, 2H), 7.24,(s, Ar-H, 2H).
Synthesis of 3,4,5-tris(n-alkyl-1-yloxy) benzyl alcohol (4). [3]
A solution of 1a8 (3.44 g, 6.61 mmol) in dry ether (8 ml) was added dropwise to a
suspension of lithium aluminum hydride (188 mg, 4.96 mmol) in dry ether (4 ml). After
the addition was completed, the mixture was allowed to stir at room temperature for 1 h.
The reaction was quenched by dropwise, addition of 10% HCl aqueous solution in an
ice-bath. The precipitate was rinsed with tetrahydrofuran. Undissolved materials were
filter off. Organic layer was separated and dried over anhydrous sodium sulfate.
Removal solvent gave white solid material, which was recrystallized from acetone to
give 4a (2.91 g, 90 %) as white crystals. The analogous compound (4b) was obtained the
similar reaction procedure by using 1a12 as a starting material instead of 1a8.
4a: 90 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 6.8 Hz, 9H), 1.20-1.38 (bs, CH2 x
12, 24H), 1.45 (m, CH2 x 3, 6H), 1.76 (m, CH2 x 3, 6H), 3.92 (t, CH2OAr, J = 6.8 Hz, 2H),
3.96 (t, CH2Oar x 2, J = 6.4 Hz, 4H), 4.59 (d, ArCH2OH, J = 6.0 Hz, 2H), 6.55 (s, Ar-H,
2H).
4b: 93 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 6.8 Hz, 9H), 1.20-1.38 (bs, CH2 x
24, 48H), 1.45 (m, CH2 x 3, 6H), 1.76 (m, CH2 x 3, 6H), 3.92 (t, CH2OAr, J = 6.8 Hz, 2H),
3.96 (t, CH2Oar x 2, J = 6.4 Hz, 4H), 4.59 (d, ArCH2OH, J = 6.0 Hz, 2H), 6.55 (s, Ar-H,
2H).
Synthesis of 3,4,5-tris(n-alkyl-1-yloxy) benzyl chloride (5). [3]
A solution of 4a (2.91 g, 5.91 mmol), thionyl chloride (982 mg, 8.27 mmol), and a
catalytic amount of N,N-dimetyl formamide (a drop) in dry dichloromethane (30 ml) was
refluxed for 0.5 h. The solvent and excess thionyl chloride was removed under a reduced
pressure. The solid residue was dissolved in ether, washed with water several times,
dried over anhydrous sodium sulfate. Removal of solvent gave 5a (2.84 g, 94.4 %) as
white crystals. The analogous compound (5b) was obtained the similar reaction
procedure by using 4b as a starting material instead of 4a.
5a: 94 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 6.8 Hz, 9H), 1.20-1.38 (bs, CH2 x
12, 24H), 1.45 (m, CH2 x 3, 6H), 1.79 (m, CH2 x 3, 6H), 3.93 (t, CH2OAr, J = 6.4 Hz, 2H),
3.96 (t, CH2OAr x 2, J = 6.4 Hz, 4H), 4.50 (s, ArCH2Cl, 2H), 6.55 (s, Ar-H, 2H).
5b: 91 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 3, J = 6.8 Hz, 9H), 1.20-1.38 (bs, CH2 x
24, 48H), 1.45 (m, CH2 x 3, 6H), 1.79 (m, CH2 x 3, 6H), 3.93 (t, CH2OAr, J = 6.4 Hz, 2H),
3.96 (t, CH2OAr x 2, J = 6.4 Hz, 4H), 4.50 (s, ArCH2Cl, 2H), 6.55 (s, Ar-H, 2H).
Synthesis of Poly(aryl ether)dendrons (2a8 and 2a12) [3]
5a (1.82 g, 3.57 mmol) was added to a suspension of 3 (219 mg, 1.19 mmol) and
potassium carbonate (1.48 g, 10.7 mmol) in dry and degassed N,N-dimethyl formamide
(36 ml) at 65 C. After the addition was completed, the mixture was heated at 65 for 3.5 h.
The reaction mixture was poured into ice-water. The precipitate was collected and
dissolved in dichloromethane. The solution was subjected column chromatography on
alumina using dichloromethane as an eluent to give 2a8 (807 mg, 41.1 % yield) as white
crystals. The analogous compound (2a12) was obtained the similar reaction procedure by
using 5b as a starting material instead of 5a.
2a8: 41 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 9, J = 6.8 Hz, 27H), 1.20-1.50(m, CH2 x
45, 90H), 1.72 (m, CH2 x 9, 18 H), 3.74 (t, CH2OAr x 2, J = 6.4 Hz, 4H), 3.87 (t, CH2OAr x
4, J = 5.2 Hz, 8H), 3.87(s,CO2CH3, 3H), 3.92 (t, 6H,CH2OAr x 3, J = 6.8 Hz, 6H), 5.02 (s,
ArCH2OAr, 6H), 6.59 (s, Ar-H, 2H), 6.62 (s,Ar-H, 4H), 7.37 (s, Ar-H, 2H).
2a12: 69 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 9, J = 6.8 Hz, 27H), 1.20-1.50(m, CH2 x
81, 162H), 1.72 (m, CH2 x 9, 18 H), 3.74 (t, CH2OAr x 2, J = 6.4 Hz, 4H), 3.87 (t, CH2OAr
x 4, J = 5.2 Hz, 8H), 3.87(s,CO2CH3, 3H), 3.92 (t, 6H,CH2OAr x 3, J = 6.8 Hz, 6H), 5.02 (s,
ArCH2OAr, 6H), 6.59 (s, Ar-H, 2H), 6.62 (s,Ar-H, 4H), 7.37 (s, Ar-H, 2H).
Synthesis of Poly(aryl ether)dendrons (2b8 and 2b12) [3]
A mixture of 2a8 (100 mg, 0.616 mmol), 10N NaOH aqueous solution (1.0 ml) and
rhtanol (10 ml) was heated at 80 C for 3h. After cooling to room temperature, the
reaction mixture was acidified by 10% HCl aqueous solution in an ice-bath. The
precipitate was collected by filtration and then dissolved in dichloromethane. The
solution was dried over anhydrous sodium sulfate. Removal of solvent gave white
crystals, which was recrystallized from ether to give 2b8 (41 mg, 41 %) as white crystals.
The analogous compound (2b12) was obtained the similar reaction procedure by using
2a12 as a starting material instead of 2a8.
2b8: 41 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 9, J = 6.8 Hz, 27H), 1.20-1.50(m, CH2 x
45, 90H), 1.73 (m, CH2 x 9, 18 H), 3.75 (t, CH2OAr x 2, J = 6.8 Hz, 4H), 3.88 (t, CH2OAr x
4, J = 6.8 Hz, 8H), 3.92 (t, 6H,CH2OAr x 3, J = 6.8 Hz, 6H), 5.02 (s, ArCH2OAr, 4H), 5.05
(s, ArCH2OAr, 2H), 6.59 (s, Ar-H, 2H), 6.62 (s,Ar-H, 4H), 7.41 (s, Ar-H, 2H).
2b12: 50 % yield. 1H-NMR (CDCl3): 0.87 (t, CH3 x 9, J = 6.8 Hz, 27H), 1.20-1.50(m, CH2 x
81, 162H), 1.73 (m, CH2 x 9, 18 H), 3.75 (t, CH2OAr x 2, J = 6.8 Hz, 4H), 3.88 (t, CH2OAr
x 4, J = 6.8 Hz, 8H), 3.92 (t, 6H,CH2OAr x 3, J = 6.8 Hz, 6H), 5.02 (s, ArCH2OAr, 4H),
5.05 (s, ArCH2OAr, 2H), 6.59 (s, Ar-H, 2H), 6.62 (s,Ar-H, 4H), 7.41 (s, Ar-H, 2H).
References
[1] Iqbal, P.; Mayanditheuar, M.; Childs, L. J.; Hannon, M. J.; Spencer, N.; Ashton, P. R.;
Preece, J. A., Materials, 2, 146-168 (2009).
[2] Yang, C.-A.; Wang, G.; Xie, H. L.; Zhang, H. L., Polymer, 31, 4503-4510 (2010).
[3] Percec, V.; Peterca、M.; Tsuda, Y.; Rosen, B. M.; Uchida, S.; Imam, M. R.; Ungar, G.;
Heiney, P. A., Chem. Eur. J., 15, 8994-9004 (2009).