Electronic supplementary material
Investigations on Photo and Electrically Switchable Asymmetric Bent-core Liquid Crystals
Murugesan Vijay Srinivasana, Palaninathan Kannana∗, Arun Royb
a. Department of Chemistry, Anna University, Chennai-600 025, India
b. Soft Condensed Matter, Raman Research Institute, Bangalore-560 080, India
2.3. Synthesis of 4-((4'-hydroxyphenylazo)phenyl)acetamide (1)
The synthesis of compound 4-((4'-hydroxyphenylazo)phenyl)acetamide was prepared
according to our previous report [15]. 4-Aminophenylacetamide (10.4g, 0.07 mol) was cooled in
ice bath, then a mixture of hydrochloric acid (16 mL) and water (16 mL) added to the reaction
mixture with constant stirring and the resultant mixture diazotized by slow addition of sodium
nitrite (4.8g, 0.07 mol) in 20 mL of water, at temperature below 5 ºC. Phenol (7.4g, 0.07 mol)
was dissolved in 10 % sodium hydroxide solution (45 mL) in round bottom flask and cooled to 5
ºC. The above reaction mixture stirred vigorously then the diazonium chloride solution was
added drop wise to the reaction mixture and kept in an ice bath for 30 min. After completion of
the reaction, the mixture was poured into water (500 mL) and acidified with aqueous
hydrochloric acid to obtain orange colored product.
The crude product is filtered and washed
well with water and resultant dried in vacuum oven at 60 ºC for 2 days (Yield: 68 %).
1:C14H13N3O2: Calcd. C, 65.17; H, 5.13; N, 16.46; O, 12.54; found C, 65.03; H, 5.22; N,
16.36; O, 13.39; FT-IR; 3308, 3040, 1601, 1585, 1429; 1H NMR (CDCl3, 400 MHz), δ (ppm):
8.1 (d, 1H, -NH-COCH3), 7.90 (d, J=8 Hz, 2H, Ar-H), 7.81 (d, J=8 Hz, 2H, Ar-H), 7.69 (d, J=8
Hz, 2H, Ar-H), 6.81 (d, J=8 Hz, 2H, Ar-H), 5.15 (s, H, -OH), 1.81 (s, 3H, -CH3).
13
C NMR
(CDCl3, 400 MHz), δ (ppm): 168.1, 160.9, 148.1, 144.9, 140.1, 124.2, 122.7, 121.1, 116.2, 22.0
and 14.6.
2.4. Synthesis of 4-((4'-hexyloxyphenylazo)phenyl)acetamide (2a)
The synthesis of compound 4-((4'-hexyloxyphenylazo)phenyl)acetamide (2a) was
prepared
according
to
our
previous
hexyloxyphenylazo)phenyl)acetamide
report
carried
[15].
The
synthesis
by
suspension
of
4-(4'of
(4-(4'-hydroxyphenylazo)phenyl)acetamide (2.5g, 0.01 mol), anhydrous K2CO3 (2.76g, 0.02
mol), 0.5 wt % of KI (0.35g) in dry acetone (80 mL) and the reaction was carried out for 24 h at
90 ºC with constant stirring. The drop wise addition of 1-bromohexane (1.65g, 0.01mol) to the
reaction mixture and refluxed for 24 h. After completion of the reaction, the mixture was filtered
and washed with excess of DMF. The filtrate was poured in to ice water and extracted using
diethyl ether, dried with anhydrous sodium sulphate. An orange colored solid was obtained after
the solvent evaporated under vacuum, then product purified by column chromatography (silica
gel, chloroform) (Yield: 2.54g, 75 %). A similar procedure was adopted for preparation of other
even numbered alkyl series such as octyl, decyl and dodecyl (2b-2d) derivatives.
2a: C20H25N3O2; Calcd. C, 70.77; H, 7.42; N, 12.38; O, 9.43; found C,70.62; H, 7.31; N,
12.48; O, 9.59. FT-IR; 3318, 3055, 2852, 1667, 1585, 1418,1258,1151.1H-NMR (CDCl3, 400
MHz), δ (ppm): 8.01 (d, 1H, -NH), 7.85 (d, J=8Hz, 2H, Ar-H), 7.80-74 (d, J=8Hz, 4H, Ar-H),
6.85 (d, J=8Hz, 2H, -Ar-H), 3.90 (m, 2H, -OCH2-), 1.93 (s, 3H, CH3-CO-), 1.73 (m, 2H, -CH2-),
1.30-1.29 (m, 6H, -CH2-), 0.9 (t, 3H, -CH3).
13
C NMR (CDCl3, 400 MHz),168.1, 158.6, 148.5,
144.2, 140.3, 123.5, 123,1, 121.0, 114.7, 68, 31, 29.5, 22.8, 22.1 and 14.0.
2.4. Synthesis of 4-((4'-octyloxyphenylazo)phenyl)acetamide (2b)
The synthesis of 4-(4'-octyloxyphenylazo)phenyl)acetamide carried by suspension of
(4-(4'-hydroxyphenylazo)phenyl)acetamide (2.5g, 0.01 mol), anhydrous K2CO3 (2.76g, 0.02
mol), 0.5 wt % of KI (0.35g) in dry acetone (80 mL) and the reaction was carried out for 24 h at
90 ºC with constant stirring. The drop wise addition of 1-bromoctane (1.93g, 0.01mol) to the
reaction mixture and refluxed for 24 h. After completion of the reaction, the mixture was filtered
and washed with excess of DMF. The filtrate was poured in to ice water and extracted using
diethyl ether, dried with anhydrous sodium sulphate. An orange colored solid was obtained after
the solvent evaporated under vacuum, then product purified by column chromatography (silica
gel, chloroform) (Yield: 2.71g, 74 %).
2b: C22H29N3O2; Calcd. C, 71.9; H, 7.95; N, 11.43; O, 8.71; found C,70.52; H, 7.35; N,
12.42; O, 9.71. FT-IR; 3317, 3052, 2852, 1664, 1579, 1414,1258,1153.1H-NMR (CDCl3, 400
MHz), δ (ppm): 8.12 (d, 1H, -NH), 7.83 (d, J=8Hz, 2H, Ar-H), 7.81-7.74 (d, J=8Hz, 4H, Ar-H),
6.86 (d, J=8Hz, 2H, -Ar-H), 3.91 (m, 2H, -OCH2-), 1.93 (s, 3H, CH3-CO-), 1.77 (m, 2H, -CH2-),
1.35-29 (m, 10H, -CH2-), 0.89 (t, 3H, -CH3). 13C NMR (CDCl3, 400 MHz), 168.5, 165.4, 160.6,
148.3, 144.2, 141.3, 123.3, 123,1, 121.3, 114.4, 68.4, 32.1, 28.1, 22.6, 22.3 and 14.1.
2.4. Synthesis of 4-((4'-decyloxyphenylazo)phenyl)acetamide (2c)
The synthesis of 4-(4'-decyloxyphenylazo)phenyl)acetamide carried by suspension of
(4-(4'-hydroxyphenylazo)phenyl)acetamide (2.5g, 0.01 mol), anhydrous K2CO3 (2.76g, 0.02
mol), 0.5 wt % of KI (0.37g) in dry acetone (80 mL) and the reaction was carried out for 24 h at
90 ºC with constant stirring. The drop wise addition of 1-bromodecane (2.2g, 0.01mol) to the
reaction mixture and refluxed for 24 h. After completion of the reaction, the mixture was filtered
and washed with excess of DMF. The filtrate was poured in to ice water and extracted using
diethyl ether, dried with anhydrous sodium sulphate. An orange colored solid was obtained after
the solvent evaporated under vacuum, then product purified by column chromatography (silica
gel, chloroform) (Yield: 2.84g, 72 %).
2c: C24H33N3O2; Calcd. C, 72.88; H, 8.41; N, 10.62; O, 8.09; found C,72.82; H, 8.51; N,
10.57; O, 8.10. FT-IR; 3317, 3053, 2851, 1667, 1585, 1415,1253,1151.1H-NMR (CDCl3, 400
MHz), δ (ppm): 8.05 (d, 1H, -NH), 7.81 (d, J=8Hz, 2H, Ar-H), 7.80-7.74 (d, J=8Hz, 4H, -Ar-H),
6.81 (d, J=8Hz, 2H, -Ar-H), 3.91 (m, 2H, -OCH2-), 1.93 (s, 3H, CH3-CO-), 1.75 (m, 2H, -CH2-),
1.31-1.27 (m, 14H, -CH2-), 0.9 (t, 3H, -CH3). 13C NMR (CDCl3, 400 MHz), 168.1, 165.3, 159.9,
148.3, 144.1, 140.5, 123.7, 123,4, 121.5, 114.4, 68.7, 30.5, 29.8, 22.6, 22.3 and 14.0.
2.4. Synthesis of 4-((4'-dodecyloxyphenylazo)phenyl)acetamide (2d)
The synthesis of 4-(4'-dodecyloxyphenylazo)phenyl)acetamide carried by suspension of
(4-(4'-hydroxyphenylazo)phenyl)acetamide (2.5g, 0.01 mol), anhydrous K2CO3 (2.76g, 0.02
mol), 0.5 wt % of KI (0.38g) in dry acetone (80 mL) and the reaction was carried out for 24 h at
90 ºC with constant stirring. The drop wise addition of 1-bromododecane (2.49 g, 0.01mol) to the
reaction mixture and refluxed for 24 h. After completion of the reaction, the mixture was filtered
and washed with excess of DMF. The filtrate was poured in to ice water and extracted using
diethyl ether, dried with anhydrous sodium sulphate. An orange colored solid was obtained after
the solvent evaporated under vacuum, then product purified by column chromatography (silica
gel, chloroform) (Yield: 2.99g, 92 %).
2d: C26H37N3O2; Calcd. C, 73.72; H, 8.80; N, 9.92; O, 7.55; found C,73.62; H, 8.81; N,
9.48; O, 8.09. FT-IR; 3320, 3053, 2985, 2851, 1665, 1575, 1415,1255,1151.1H-NMR (CDCl3,
400 MHz), δ (ppm): 8.07 (d, 1H, -NH), 7.81 (d, J=8Hz, 2H, Ar-H), 7.82-7.71 (d, J=8Hz, 4H, ArH), 6.81 (d, J=8Hz, 2H, Ar-H), 3.91 (m, 2H, -OCH2-), 1.93 (s, 3H, CH3-CO-), 1.77 (m, 2H, CH2-), 1.33-1.26 (m, 18H, -CH2-), 0.89 (t, 3H, -CH3).
13
C NMR (CDCl3, 400 MHz), 168.5,
165.2, 159.8, 148.1, 144.1, 140.1, 125.1, 123.2, 121.7, 113.9, 67.5, 32.4, 29.5, 22.4, 22.3 and
14.1.
2.5. Synthesis of 4-(4'-hexyloxyphenylazo) aniline (3a)
Synthesis of 4-(4'-hexyloxyphenylazo) aniline (3a) was prepared according to our
previous report [15]. The hydrolysis of 4-((4'-hexyloxyphenylazo)phenyl)acetamide (3.38g, 0.01
mol) carried out in ethanol (100 mL) and conc. HCl (3 mL, 0.03 mol) then the reaction mixture
was refluxed for 4 h. After completion of the reaction, the mixture poured into water (500 mL)
and neutralized with saturated NaHCO3 solution and extracted using chloroform, dried with
sodium sulphate. The crude product was recrystallized from ethanol to obtained dark brown
color 4-(4'-hexyloxyphenylazo) aniline (Yield: 2.82g, 95 %). A similar procedure was adopted
for preparation of other even numbered alkyl series such as octyl, decyl and dodecyl (3b-3d)
derivatives.
3a: C18H23N3O; Calcd. C, 72.70; H, 7.8; N, 14.13; O, 5.38 found C, 72.68; H, 7.81; N,
14.11; O, 5.40. FT-IR; 3465, 3421, 3057, 2856, 1590, 1474,1253, 1145. 1H-NMR (CDCl3, 400
MHz), δ (ppm): 7.77 (d, J=8Hz, 2H, Ar-H), 7.60 (d, J=8Hz, 2H, Ar-H), 6.85-6.66 (d, J=8Hz, 4H,
Ar-H), 3.96 (m, 2H, Ar-NH2), 3.70 (m, 2H, -OCH2-), 1.73 (d, 2H, -CH2-),1.31-1.26 (m, 6H, CH2-), 0.8 (t, 3H, -CH3). 13C-NMR (CDCl3, 400 MHz), 158.4, 150.4, 144.2, 142.9, 141.8, 122.5,
116.1, 114.0, 67.5, 27.2, 25.3, 22.2 and 14.0.
2.5. Synthesis of 4-(4'-octyloxyphenylazo) aniline (3b)
The hydrolysis of 4-((4'-octyloxyphenylazo)phenyl)acetamide (3.67g, 0.01 mol) carried
out in ethanol (100 mL) and conc. HCl (3 mL, 0.03 mol) then the reaction mixture was refluxed
for 4 h. After completion of the reaction, the mixture poured into water (500 mL) and neutralized
with saturated NaHCO3 solution and extracted using chloroform, dried with sodium sulphate.
The crude product was recrystallized from ethanol to obtained dark brown color 4-(4'octyloxyphenylazo)aniline (Yield: 2.9g, 92 %).
3b: C20H27N3O; Calcd. C, 73.81; H, 8.36; N, 12.91; O, 4.92; found C, 73.68; H, 8.81; N,
12.51; O, 4.80. FT-IR; 3462, 3057, 2986, 2856, 1592, 1464, 1252, 1141. 1H-NMR (CDCl3, 400
MHz), δ (ppm): 7.78 (d, J=8Hz, 2H, Ar-H), 7.61 (d, J=8Hz, 2H, Ar-H), 6.84-6.66 (d, J=8Hz, 4H,
Ar-H), 3.95 (m, 2H, Ar-NH2), 3.79 (m, 2H, -OCH2-), 1.77 (d, 2H, -CH2-),1.31-1.28 (m, 10H, CH2-), 0.89 (t, 3H, -CH3).
13
C-NMR (CDCl3, 400 MHz), 159.4, 150.1, 144.5, 142.3, 141.1,
122.1, 116.5, 114.2, 67.4, 28.2, 25.4, 22.2 and 13.8.
2.5. Synthesis of 4-(4'-decyloxyphenylazo) aniline (3c)
The hydrolysis of 4-((4'-decyloxyphenylazo)phenyl)acetamide (3.95g, 0.01 mol) carried
out in ethanol (100 mL) and conc. HCl (3 mL, 0.03 mol) then the reaction mixture was refluxed
for 4 h. After completion of the reaction, the mixture poured into water (500 mL) and neutralized
with saturated NaHCO3 solution and extracted using chloroform, dried with sodium sulphate.
The crude product was recrystallized from ethanol to obtained dark brown color 4-(4'decyloxyphenylazo) aniline (Yield: 3.3g, 96 %).
3c: C22H31N3O; Calcd. C, 74.75; H, 8.84; N, 11.89; O, 4.53 found C, 74.68; H, 8.81; N,
11.85; O, 4.66. FT-IR; 3461, 3425, 3055, 2983, 2851, 1595, 1473,1253, 1143. 1H-NMR (CDCl3,
400 MHz), δ (ppm): 7.80 (d, J=8Hz, 2H, Ar-H), 7.63 (d, J=8Hz, 2H, Ar-H), 6.85-6.69 (d, J=8Hz,
4H, Ar-H), 3.97 (m, 2H, Ar-NH2), 3.70 (m, 2H, -OCH2-), 1.81 (d, 2H, -CH2-),1.31-1.25 (m, 14H,
-CH2-), 0.88 (t, 3H, -CH3).
13
C-NMR (CDCl3, 400 MHz): 159.7, 150.1, 144.1, 142.3, 141.5,
122.3, 115.7, 114.9, 67.4, 27.3, 24.3, 23.1 and 14.1.
2.5. Synthesis of 4-(4'-dodecyloxyphenylazo) aniline (3d)
The hydrolysis of 4-((4'-dodecyloxyphenylazo)phenyl)acetamide (4.23g, 0.01 mol)
carried out in ethanol (100 mL) and conc. HCl (3 mL, 0.03 mol) then the reaction mixture was
refluxed for 4 h. After completion of the reaction, the mixture poured into water (500 mL) and
neutralized with saturated NaHCO3 solution and extracted using chloroform, dried with sodium
sulphate. The crude product was recrystallized from ethanol to obtained dark brown color 4-(4'dodecyloxyphenylazo) aniline (Yield: 3.61g, 95 %).
3d: C18H23N3O; Calcd. C, 75.55; H, 9.25; N, 11.01; O, 4.19 found C, 75.69; H, 9.21; N,
11.11; O, 3.99. FT-IR; 3461, 3057, 2984, 2856, 1592, 1414,1253, 1141. 1H-NMR (CDCl3, 400
MHz), δ (ppm): 7.79 (d, J=8Hz, 2H, Ar-H), 7.69 (d, J=8Hz, 2H, Ar-H), 6.85-6.67 (d, J=8Hz, 4H,
Ar-H), 3.99 (m, 2H, Ar-NH2), 3.65 (m, 2H, -OCH2-), 1.81 (d, 2H, -CH2-), 1.31-1.29 (m, 18H, CH2-), 0.89 (t, 3H, -CH3).
13
C NMR (CDCl3, 400 MHz), 159.1, 151.3, 144.1, 142.1, 141.1,
122.1, 116.1, 114.0, 68.1, 29.2, 25.3, 22.1 and 14.1.
2.5.
Synthesis of 4-((3-formylphenoxy)carbonyl)phenyl4-hexyloxybenzoate (7a)
The 4-((3-formylphenoxy)carbonyl)phenyl4-hexyloxybenzoate was synthesized by
esterification reaction of 4-(4'-hexyloxybenzoyloxy)benzoic acid
(3.42g, 0.01 mol),
DCC (2.47g, 0.012 mol) with 3-hydroxybenzaldehyde (1.22g, 0.01mol), 5 wt % of DMAP
(0.046g) in dry dichloromethane (50 ml) and reaction mixture was stirred for 12 h. After
completion of reaction, the precipitated N, N′-9-dicyclohexylurea was filtered, washed with
excess of dichloromethane and filtrate concentrated in a rotary evaporator. The residue was
purified by silica gel column using chloroform as eluent. (Yield: 3.7g, 85%) A similar procedure
was adopted for preparation of other even numbered alkyl series such as octyl, decyl and dodecyl
(7b-7d) derivatives.
7a : C27H26O6: Calcd C, 72.63; H, 5.87; O, 21.50; found C, 72.61; H, 5.81; O, 21.58. FTIR (KBr pellet, cm-1): 2916, 2851, 1736, 1603, 1262. 1H NMR (CDCl3, 400 MHz) δ (ppm): 9.77
(s, 1H, -CHO), 8.20-8.06 (d, J=8Hz, 4H, Ar-H), 7.73 (d, J=8Hz, 1H, Ar-H), 7.52 (s, 1H, Ar-H),
7.50 (t, J=8Hz, 1H, Ar-H), 7.43 (d, J=8Hz, 1H, Ar-H), 7.30 (d, J=8Hz, 2H, Ar-H), 6.9 (d,
J=8.4Hz, 2H, Ar-H), 3.79 (t, 2H, -OCH2), 1.79 (m, 2H, -CH2-), 1.33-1.29 (m, 6H, -CH2-), 0.91(t,
3H, -CH3).
13
C NMR (CDCl3, 400 MHz) δ (ppm): 191.0, 165.2, 162.7, 156.5, 151.9, 137.2,
130.7, 130.2, 127.6, 122.4, 114.6, 68.4, 31.9, 29.8, 22.5 and 14.4.
2.5.
Synthesis of 4-((3-formylphenoxy)carbonyl)phenyl 4-octyloxybenzoate (7b)
The 4-((3-formylphenoxy)carbonyl)phenyl 4-octyloxybenzoate was synthesized by
esterification
reaction
of
4-(4'-octyloxybenzoyloxy)benzoic
acid
(3.7g,
0.01
mol),
DCC (2.47g, 0.012 mol) with 3-hydroxybenzaldehyde (1.22g, 0.01mol), 5 wt % of DMAP
(0.047g) in dry dichloromethane (50 ml) and reaction mixture was stirred for 12 h. After
completion of reaction, the precipitated N, N′-9-dicyclohexylurea was filtered, washed with
excess of dichloromethane and filtrate concentrated in a rotary evaporator. The residue was
purified by silica gel column using chloroform as eluent. (Yield: 3.7g, 80%).
7b : C29H30O6: Calcd C, 73.40; H, 6.37; 20.23; found C, 73.31; H, 6.31; O, 20.38. FT-IR
(KBr pellet, cm-1): 2917, 2855, 1734, 1603, 1411, 1262. 1H NMR (CDCl3, 400 MHz) δ (ppm):
9.78 (s, 1H, -CHO), 8.18-8.06 (d, J=8Hz, 4H, Ar-H), 7.75 (d, J=8Hz, 1H, Ar-H), 7.51 (s, 1H,
Ar-H), 7.48 (t, J=8Hz, 1H, Ar-H), 7.41 (d, J=8Hz, 1H, Ar-H), 7.33 (d, J=8Hz, 2H, Ar-H), 6.91
(d, J=8.4Hz, 2H, Ar-H), 3.78 (t, 2H, -OCH2), 1.88 (m, 2H, -CH2-), 1.33-1.29 (m, 10H, -CH2-),
0.89 (t, 3H, -CH3).
13
C NMR (CDCl3, 400 MHz) δ (ppm): 191.3, 164.5, 162.3, 156.4, 151.5,
145.4, 136.1, 131.4, 130.2, 127.6, 122.4, 114.6, 68.4, 31.9, 29.8, 22.5 and 14.1.
2.5.
Synthesis of 4-((3-formylphenoxy)carbonyl)phenyl 4-decyloxybenzoate (7c)
The 4-((3-formylphenoxy)carbonyl)phenyl 4-decyloxybenzoate was synthesized by
esterification reaction of 4-(4'-decyloxybenzoyloxy)benzoic acid
(3.98g, 0.01 mol),
DCC (2.47g, 0.012 mol) with 3-hydroxybenzaldehyde (1.22g, 0.01mol), 5 wt % of DMAP
(0.049g) in dry dichloromethane (50 ml) and reaction mixture was stirred for 12 h. After
completion of reaction, the precipitated N, N′-9-dicyclohexylurea was filtered, washed with
excess of dichloromethane and filtrate concentrated in a rotary evaporator. The residue was
purified by silica gel column using chloroform as eluent. (Yield: 4.17g, 83%).
7c : C31H34O6: Calcd C, 74.08; H, 4.82; O, 19.10; found C, 74.11; H, 4.81; O, 21.08. FTIR (KBr pellet, cm-1): 2912, 2855, 1736, 1603, 1412, 1261. 1H NMR (CDCl3, 400 MHz) δ
(ppm): 9.81 (s, 1H, -CHO), 8.21-8.09 (d, J=8Hz, 4H, Ar-H), 7.71 (d, J=8Hz, 1H, Ar-H), 7.51 (s,
1H, Ar-H), 7.48 (t, J=8Hz, 1H, Ar-H), 7.42 (d, J=8Hz, 1H, Ar-H), 7.31 (d, J=8Hz, 2H, Ar-H),
6.91 (d, J=8.4Hz, 2H, Ar-H), 3.78 (t, 2H, -OCH2), 1.89 (m, 2H, -CH2-), 1.33-1.27 (m, 14H, CH2-), 0.89 (t, 3H, -CH3).
C NMR (CDCl3, 400 MHz) δ (ppm): 192.1, 165.4, 162.3, 156.4,
13
151.9, 138.2, 130.7, 130.1, 128.6, 121.9, 113.1, 68.5, 31.7, 29.4, 22.1 and 14.1.
2.5.
Synthesis of 4-((3-formylphenoxy)carbonyl)phenyl 4-dodecyloxybenzoate (7d)
The 4-((3-formylphenoxy)carbonyl)phenyl 4-dodecyloxybenzoate was synthesized by
esterification reaction of 4-(4'-dodecyloxybenzoyloxy)benzoic acid
(4.26g, 0.01 mol),
DCC (2.47g, 0.012 mol) with 3-hydroxybenzaldehyde (1.22g, 0.01mol), 5 wt % of DMAP
(0.5g)
in dry dichloromethane (50 ml) and reaction mixture was stirred for 12 h.
After
completion of reaction, the precipitated N, N′-9-dicyclohexylurea was filtered, washed with
excess of dichloromethane and filtrate concentrated in a rotary evaporator. The residue was
purified by silica gel column using chloroform as eluent. (Yield: 4.54g, 86%).
7d : C33H38O6: Calcd C, 74.69; H, 7.22; O, 18.09; found C, 74.58; H, 7.81; O, 17.61. FTIR (KBr pellet, cm-1): 2921, 2855, 1734, 1611, 1412, 1261. 1H NMR (CDCl3, 400 MHz) δ
(ppm): 9.88 (s, 1H, -CHO), 8.21-8.05 (d, J=8Hz, 4H, Ar-H), 7.75 (d, J=8Hz, 1H, Ar-H), 7.53 (s,
1H, Ar-H), 7.50 (t, J=8Hz, 1H, Ar-H), 7.44 (d, J=8Hz, 1H, Ar-H), 7.32 (d, J=8Hz, 2H, Ar-H),
6.94 (d, J=8.4Hz, 2H, Ar-H), 4.01 (t, 2H, -OCH2), 1.89 (m, 2H, -CH2-), 1.33-1.28 (m, 18H, CH2-), 0.91(t, 3H, -CH3).
13
C NMR (CDCl3, 400 MHz) δ (ppm): 192.3, 165.3, 162.1, 156.4,
151.3, 137.3, 130.1, 129.1, 127.6, 121.4, 113.1, 67.3, 31.5, 29.7, 23.1 and 14.1.
2.6.
Synthesis of 3-(4-(4'-hexyloxybenzoyloxy)benzoyloxy)phenyl4-((4-(4hexyloxyphenylazo)phenylimino)methyl)benzoate (8a)
A
typical
procedure
for
the
synthesis
of
8a-8d
is
as
follows:
4-(4'-hexyloxyphenylazo) aniline (1.9g, 0.0064 mol) and 3-(4-(4'-hexyloxybenzoyloxy)
benzoyloxy)phenyl-4-formylbenzoate (2.84g, 0.0064 mol) was dissolved in ethanol (50 mL) then
reaction mixture refluxed until yellow color product precipitated out. After completion of
reaction, the desired product was filtered and washed with ethanol, then recrystallized from
ethanol to get yellowish brown powder (Yield: 3.29g, 71%). A similar procedure was adopted
for preparation of other even numbered alkyl series such as octyl, decyl and dodecyl (8b-8d)
derivatives.
8a: C44H47N3O6: Calcd. C, 74.46; H, 6.53; N, 5.79; O, 13.22; found C, 74.31; H, 6.48; N,
5.79; O, 13.42. FT-IR; 3471, 2922, 2852, 1734, 1602, 1474, 1413, 1253, 1116; 1H- NMR
(CDCl3, 400 MHz), δ (ppm): 8.59 (s, H, -CH=N-), 8.30-8.19 (d, J=8Hz, 4H, Ar-H), 7.95(d,
J=8Hz, 2H, Ar-H), 7.81(d, J=8Hz, 2H, Ar-H), 7.60 (q, J1=4Hz, J2=8Hz, 1H, Ar-H), 7.53 (d, 2H,
Ar-H), 7.51 (s, 1H, Ar-H), 7.40 (t, J=8Hz, 1H, Ar-H), 7.30 (d, J=8Hz, 2H,-Ar-H), 7.28 (m, 1H,
Ar-H), 6.98-6.72 (dd, J=8Hz, 4H, Ar-H), 4.08 (m, 4H, -OCH2-), 1.85 (d, 4H, -CH2-),1.33-1.28
(m, 12H, -CH2-), 0.89 (t, 6H, -CH3). 13C NMR (CDCl3, 400 MHz): 166.5, 165.3, 158.9, 156.3,
151.2, 148.1, 142.1, 135.8, 131.8, 129.8, 127.4, 124.4, 122.6, 121.9, 119.4, 118.1, 64.6, 33.9,
27.9, 22.4, 19.4 and 14.1.
2.6.
Synthesis of 3-(4-(4'-octyloxybenzoyloxy)benzoyloxy)phenyl4-((4-(4octyloxyphenylazo)phenylimino)methyl)benzoate (8b)
4-(4'-8-octyloxyphenylazo) aniline (2.08g, 0.0064 mol) and 3-(4-(4'-octyloxybenzoyloxy)
benzoyloxy)phenyl-4-formylbenzoate (3.03g, 0.0064 mol) was dissolved in ethanol (50 mL) then
reaction mixture refluxed until yellow color product precipitated out. After completion of
reaction, the desired product was filtered and washed with ethanol, then recrystallized from
ethanol to get yellowish brown powder (Yield: 3.65g, 73%).
8b: C49H55N3O6: Calcd. C, 75.26; H, 7.09; N, 5.37; O, 12.28; found C, 75.31; H, 7.08; N,
5.47; O, 12.14. FT-IR; 3464, 2935, 2854, 1733, 1605, 1474, 1411, 1251, 1116; 1H- NMR
(CDCl3, 400 MHz), δ (ppm): 8.55 (s, H, -CH=N-), 8.31-8.19 (d, J=8Hz, 4H, Ar-H), 7.94(d,
J=8Hz, 2H, Ar-H), 7.83(d, J=8Hz, 2H, Ar-H), 7.61 (q, J1=4Hz, J2=8Hz, 1H, Ar-H), 7.53 (d, 2H,
Ar-H), 7.53 (s, 1H, Ar-H), 7.41 (t, J=8Hz, 1H, Ar-H), 7.30 (d, J=8Hz, 2H,-Ar-H), 7.27 (m, 1H,
Ar-H), 6.98-6.71 (dd, J=8Hz, 4H, Ar-H), 4.01 (m, 4H, -OCH2-), 1.88 (d, 4H, -CH2-),1.33-1.28
(m, 20H, -CH2-), 0.89 (t, 6H, -CH3). 13C NMR (CDCl3, 400 MHz): 165.4, 159.9, 156.4, 151.1,
148.5, 144.1, 135.1, 132.6, 128.9, 127.3, 124.4, 122.1, 121.5, 119.1, 118.5, 66.5, 33.1, 27.4, 22.1,
18.1 and 14.0.
2.6.
Synthesis of 3-(4-(4'-decyloxybenzoyloxy)benzoyloxy)phenyl4-((4-(4decyloxyphenylazo)phenylimino)methyl)benzoate (8c)
4-(4'-decyloxyphenylazo)
aniline
(2.25g,
0.0064
mol)
and
3-(4-(4'-
decyloxybenzoyloxy)benzoyloxy)phenyl-4-formylbenzoate (3.21g, 0.0064 mol) was dissolved in
ethanol (50 mL) then reaction mixture refluxed until yellow color product precipitated out. After
completion of reaction, the desired product was filtered and washed with ethanol, then
recrystallized from ethanol to get yellowish brown powder (Yield: 4.02g, 75%).
8c: C53H63N3O6: Calcd. C, 75.96; H, 7.58; N, 5.01; O, 12.28; found C, 75.81; H, 7.68; N,
5.10; O, 11.41. FT-IR; 3461, 2933, 2854, 1734, 1604, 1464, 1411, 1251, 1115; 1H- NMR
(CDCl3, 400 MHz), δ (ppm): 8.55 (s, H, -CH=N-), 8.32-8.17 (d, J=8Hz, 4H, Ar-H), 7.93(d,
J=8Hz, 2H, Ar-H), 7.80(d, J=8Hz, 2H, Ar-H), 7.64 (q, J1=4Hz, J2=8Hz, 1H, Ar-H), 7.56 (d, 2H,
Ar-H), 7.50 (s, 1H, Ar-H), 7.41 (t, J=8Hz, 1H, Ar-H), 7.32 (d, J=8Hz, 2H,-Ar-H), 6.98 (m, 1H,
Ar-H), 6.88-6.72 (dd, J=8Hz, 4H, Ar-H), 3.98 (m, 4H, -OCH2-), 1.81 (d, 4H, -CH2-),1.33-1.27
(dd, 36H, -CH2-), 0.89 (t, 6H, -CH3). 13C NMR (CDCl3, 400 MHz): 165.1, 160.1, 155.4, 151.3,
147.3, 142.4, 135.1, 131.3, 128.8, 127.4, 125.4, 122.1, 121.4, 119.1, 118.5, 66.5, 33.5, 28.1, 21.3,
18.4 and 13.8.
2.6.
Synthesis of 3-(4-(4'-dodecyloxybenzoyloxy)benzoyloxy)phenyl4-((4-(4dodecyloxyphenylazo)phenylimino)methyl)benzoate (8d)
4-(4'-dodecyloxyphenylazo)aniline
(2.44g,
0.0064
mol)
and
3-(4-(4'-
dodecyloxybenzoyloxy)benzoyloxy)phenyl-4-formylbenzoate (3.39g, 0.0064 mol) was dissolved
in ethanol (50 mL) then reaction mixture refluxed until yellow color product precipitated out.
After completion of reaction, the desired product was filtered and washed with ethanol, then
recrystallized from ethanol to get yellowish brown powder (Yield: 4.06g, 71%).
8d: C57H71N3O6: Calcd. C, 76.56; H, 8.0; N, 4.74; O, 10.74; found C, 76.55; H, 7.88; N,
4.79; O, 10.78. FT-IR; 3473, 2925, 2852, 1731, 1606, 1474, 1413, 1253, 1115; 1H- NMR
(CDCl3, 400 MHz), δ (ppm): 8.53 (s, H, -CH=N-), 8.31-8.19 (d, J=8Hz, 4H, Ar-H), 7.96(d,
J=8Hz, 2H, Ar-H), 7.88 (d, J=8Hz, 2H, Ar-H), 7.61 (q, J1=4Hz, J2=8Hz, 1H, Ar-H), 7.53 (d, 2H,
Ar-H), 7.51 (s, 1H, Ar-H), 7.43 (t, J=8Hz, 1H, Ar-H), 7.31 (d, J=8Hz, 2H,-Ar-H), 7.28 (m, 1H,
Ar-H), 6.99-6.72 (dd, J=8Hz, 4H, Ar-H), 4.03 (m, 4H, -OCH2-), 1.81 (d, 4H, -CH2-),1.33-1.28
(m, 36H, -CH2-), 0.89 (t, 6H, -CH3). 13C NMR (CDCl3, 400 MHz): 165.2, 160.9, 155.4, 151.1,
145.8, 143.4, 135.2, 131.8, 129.3, 128.1, 123.8, 122.7, 121.3, 118.7, 114.3, 64.5, 33.7, 27.8, 22.3,
19.4 and 14.3.
S. 1 Microphotographs of B2 phase in 8d under the application of +75 V (D.C. electric fields,
sample thickness 8 μm, temperature 133 ºC).
S. 2 Microphotographs of B2 phase in 8d under the application of -75 V (D.C. electric fields,
sample thickness 8 μm, temperature 133 ºC).
S. 3 Microphotographs of B2 phase in 8d under the application of 0 V (D.C. electric fields,
sample thickness 8 μm, temperature 133 ºC).
S. 4 Absorption spectra of compound 9 with different exposure time of UV light.
S. 5 Absorption spectra of compound 10 with different exposure time of UV light.