B. Shrimant et al.
Reactive and Functional Polymers 133 (2018) 153–160
unit, namely, 4,4′-(spiro[fluorene-9,9′-xanthene]-2′,7′-diyl)bis(ben-
zene-1,2-diol) (THSFX) was designed and synthesized. Homopolymer
was synthesized by polycondensation of THSFX with 2,3,5,6-tetra-
fluoroterephthalonitrile (TFTPN) via double aromatic nucleophilic
substitution reaction. In addition, copolymers with intrinsic micro-
porosity were synthesized by polycondenstaion of varying compositions
of THSFX and 5,5′,6,6′-tetrahydroxy-3,3,3′,3′-tetramethyl-1,1′-spir-
Yield: 14.8 g, 30%; Melting Point: 218 °C; IR: 1260 (C-O-C) and
1
1095 (Ar-Br);
6
H NMR (200 MHz, DMSO-d ,), δ(ppm): 8.0 (d,
J = 10 Hz, 2H, Ar-H), 7.45–7.41 (m, 4H, Ar-H), 7.30–7.27 (m, 4H, Ar-
H), 7.13 (d, 2H, Ar-H), 6.23 (s, 2H, Ar-H).); 13C-NMR (50 MHz, DMSO-
d , δ/ppm): 153.3, 149.7, 138.9, 131.7, 129.1, 129.0, 128.8, 126.4,
6
125.2, 120.9, 119.4, 115.1, 53.2; HRMS: calcd. for C25
487.9406, found: 487.9397.
2
H14Br O:
1
obisindane (TTSBI) with TFTPN. Polymers were characterized by IR, H
1
3
and C NMR spectroscopy, GPC, XRD, TGA, and N
2
adsorption and
2.3.2. Synthesis of tetramethoxyxanthene2′,7′-bis(3,4-dimethoxyphenyl)
spiro[fluorene-9,9′-xanthene] (TMSFX)
Into a Schlenk tube were charged DBSFX (5 g, 10.2 mmol), 2,4-di-
methoxyphenylboronic acid (4.08 g, 22.4), potassium carbonate
desorption. Furthermore, the gas permeation properties of soluble PIMs
were evaluated and the influence of SFX units on physical and gas
permeation properties was investigated.
(
8.28 g) and toluene (40 mL) and the reaction mixture was degassed for
2
. Experimental part
30 min. Tetrakis(triphenylphosphine)palladium (0) (0.58 g, 0.5 mmol)
was added and the reaction mixture was degassed for 10 min. The re-
action mixture was heated at 100 °C for 20 h. After completion of re-
action (monitored by TLC), the reaction mixture was cooled to room
temperature and extracted with ethyl acetate. The ethyl acetate solu-
tion was washed with brine and was evaporated on a rotary evaporator.
The crude product was purified by column chromatography on silica gel
using pet ether: ethyl acetate (70:30, v/v) as eluent to obtain TMSFX as
a white solid.
2.1. Materials
4
-Bromophenol (Aldrich), 9-fluorenone (Aldrich), methanesulfonic
acid (Aldrich), 3,4-dimethoxyphenylboronic acid, tetrakis(triphenyl-
phosphine)palladium(0) (Pd(PPh ), potassium carbonate (Aldrich),
BBr in dichloromethane (Aldrich) and 2,3,5,6-tetra-
fluoroterephthalonitrile (TFTPN, Aldrich) were used as received. 2′,7′-
Dibromospiro[fluorene-9,9′-xanthene] (DBSFX) was synthesized ac-
cording to the reported procedure [34]. 3,3,3′,3′,-Tetra-
methylspirobisindane-5,5′,6,6′-tetraol (TTSBI) was purified by re-
crystallization from a mixture of methanol and dichloromethane
3 4
)
3
1
Yield: 4.1 g, 66%; Melting Point: 254 °C; IR: 1248 (C-O-C); H NMR
(200 MHz, DMSO-d
H), 7.31 (d, 2H, Ar-H), 7.27 (d, 2H, Ar-H), 7.25 (d, 2H, Ar-H), 6.76 (d,
6H, Ar-H), 6.59 (d, 2H, Ar-H), 6.57 (dd, 2H, Ar-H), 3.84 (s, 6H, -CH ),
3 3
3.81 (s, 6H, -CH ); C-NMR (50 MHz, CDCl , δ/ppm): 154.5, 150.7,
6
, δ/ppm): 7.81 (d, 2H, Ar-H), 7.41–7.38 (m, 4H, Ar-
3
13
(
DCM). Toluene, DCM, chloroform (CHCl
3
), tetrahydrofuran (THF),
N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMAc)
were purchased from Merck India and were purified standard proce-
dures before use.
148.9, 148.2, 139.7, 136.2, 133.4, 128.3, 127.8, 126.6, 126.0, 125.6,
125.3, 120.0, 118.9, 117.0, 111.2, 110.2, 55.9, 55.8, 54.8.; HRMS:
calcd. for C41
H
32
O
5
: 604.2244, found: 604.2239.
2.2. Characterization
2.3.3. Synthesis
of tetrahydroxyxanthene4,4′-(spiro[fluorene-9,9′-
xanthene]-2′,7′-diyl)bis (benzene-1,2-diol) (THSFX)
Melting points were measured using electrothermal MEL-TEMP
Into a two necked round bottom flask equipped with a magnetic
stirrer bar, a nitrogen inlet and an addition funnel were charged TMSFX
(4 g, 6.6 mml) and dichloromethane (150 mL). To the reaction mixture,
−1
apparatus. Infrared spectra were recorded in the range 4000–600 cm
using Bruker a-T spectrophotometer. 1H NMR and C NMR spectra
13
were recorded in CDCl
3
or DMSO-d
6
using Bruker-AV 200 MHz spec-
3
BBr in dichloromethane (10.2 mL, 26.4 mmol) was added dropwise
trometer. Chemical shifts were recorded in parts per million (ppm)
using tetramethylsilane as a reference. High resolution mass spectro-
scopy (HRMS) analysis data were obtained on Thermo scientific Q-ex-
acative instrument. Molecular weights and dispersity values of PIMs
were determined by gel permeation chromatography (GPC) equipped
with spectra series UV 100 and spectra system RI 150 detectors using
chloroform as an eluent and polystyrene as a standard. X-Ray dif-
fractograms of powder samples were recorded by a Rigaku Dmax 2500
over a period of 15 min at 0 °C and then stirred at room temperature for
12 h. The reaction mixture was quenched by addition of water and was
extracted with ethyl acetate. The ethyl acetate solution was washed
with brine and was evaporated on a rotary evaporator. The crude
product was purified by column chromatography on silica gel using pet
ether: ethyl acetate (50:50, v/v) as eluent to obtain THSFX as a col-
ourless solid.
−1
Yield: 3.2 g, 88%; Melting Point: 264 °C; IR: 3428 and 3260 cm
(-OH); 1H NMR (200 MHz, DMSO-d
, δ/ppm): 8.96 (s, 2H, Ar-H), 8.94
−
1
using Cu Kα radiation with scan rate of 2° min . Thermo gravimetric
6
−
1
analysis (TGA) was performed at a heating rate of 10 °C min under N
2
(s, 2H), 8.04 (d, 2H, Ar-H), 7.48–7.43 (t, 2H, Ar-H), 7.41 (dd, 2H, Ar-
in the range from 30 to 800 °C using Perkin-Elmer TGA-7 system.
H), 7.34 (d, 2H, Ar-H), 7.29 (t, 2H, Ar-H), 7.18 (d, 2H, Ar-H), 6.65 (d,
Differential scanning calorimetry (DSC) was performed on DSC Q10
2H, Ar-H). 6.53 (d, 2H, Ar-H), 6.49 (dd, 2H, Ar-H), 6.34 (d, 2H, Ar-H);
C-NMR (50 MHz, CDCl , δ/ppm): 154.4, 149.6, 145.4, 144.9, 139.1,
3
135.8, 130.4, 128.7, 128.3, 126.3, 125.2, 124.6, 124.2, 120.6, 117.2,
−1
13
system in the range from 30 to 390 °C at a heating rate of 10 °C min
under N . Nitrogen adsorption/desorption measurements of PIM pow-
2
ders were made using Micrometrics ASAP 2020 at 77 K. Samples were
degassed at 120 °C under high vacuum before analysis.
117.0, 116.0, 113.1, 53.9.; HRMS: calcd. for C37
found: 549.1686.
25 5
H O : 549.1697,
2
2
.3. Synthesis
2.3.4. Polymerization
Into a 100 mL three-necked round-bottom flask equipped with a
magnetic stirring bar and a nitrogen inlet were charged THSFX (1.5 g,
4.25 mmol), TFTPN (0.85 g, 4.25 mmol) and DMAc (15 mL). The reac-
tion mixture was heated at 120 °C for 5 min and then potassium car-
bonate (3.5 g, 25.53 mmol) was added in one portion (color changed
from orange-red to orange- yellow). The reaction mixture was heated at
150 °C for 5 min; 2 mL toluene was added and stirred at same tem-
perature until the solution became viscous (10–20 min). The resulting
viscous solution was precipitated into methanol; yellow powder was
collected by filtration, washed with hot water and methanol and dried
at 100 °C for four days.
.3.1. Synthesis of 2′,7′-dibromospiro[fluorene-9,9′-xanthene] (DBSFX)
Into a two-necked round-bottom flask equipped with a magnetic
stirring bar and a nitrogen inlet were charged 4-bromophenol (17.3 g,
00 mmol), 9-fluorenone (3.38 g, 10 mmol) and methanesulfonic acid
2.6 mL, 3.84 g, 40 mmol). The reaction mixture was heated at 150 °C
1
(
for 12 h, cooled and precipitated into methanol. The crude product was
then extracted with ethyl acetate, washed with brine and was con-
centrated on a rotary evaporator. The crude product was purified by
column chromatography on silica gel using pet ether and ethyl acetate
(
98: 2, v/v) as eluent to obtain DBSFX as a white solid.
154