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tained at RT unless otherwise specified, standard 1 mm or 10 mm
path quartz cuvettes were used depending on sample concentra-
tion. 10 mm path length cuvettes were used for all spectroscopic
investigations unless specified otherwise. Quartz slides were used
for thin film spectroscopic measurements. TGA was carried out on
a Perkin–Elmer STA6000 simultaneous thermal analyser with an in-
ternal microbalance and thermocouple. DSC analyses were per-
formed on Q100 from TA instruments coupled to a refrigerated
cooling system (RCS90) at a scanning rate of 108Cminꢀ1. The
sample holders used were nonhermetic aluminium pans, and the
sample weight was obtained using a XT220A Precisa microbalance.
TEM was performed on a JEOL 1200EX TEM MK2 with a tungsten
filament at an operating frequency of 120 kV. The instrument is
equipped with a MegaView II digital camera using Soft Imaging
Systems 3.0 image software. Samples were prepared by dropcast-
ing onto carbon-coated copper grids on Teflon film and set to dry
under ambient conditions unless otherwise stated. XRD (WAXS)
data was recorded with CuKa radiation (l=1.5418 A) on a Bruker
D8 advance powder diffractometer fitted with a 0.6 mm fixed di-
vergence slit, knife-edge collimator and a LynxEye detector. POM
images were obtained using a Nikon BX-50 microscope fitted with
an Olympus C-5060 wide zoom digital camera. Films prepared by
solvent annealing from DMSO were dried at 758C for 12 h. BTPPP
samples prepared from acetonitrile for POM were of unknown con-
centration.
Figure 11. POM images of BTPPP: a) Solvent-annealed film from DMSO
b) prepared by peripheral evaporation from acetonitrile, scale bar=50 mm.
General procedure for the synthesis of N,N’-bis[2-(dimethy-
lamino)-3-(phenyl)propyl]perylene diimide
molecular chirality was not observed for the uncharged precur-
sor BDPPP. Temperature-dependent UV/Vis and CD studies
were used to follow the transition to the molecularly dissolved
phase at elevated temperatures; this process is reversible, as
indicated by the nearly identical gradient of the temperature-
dependent spectra obtained from CD spectroscopy. The UV/Vis
data was fitted to an isodesmic model of assembly, and stack
lengths of aggregates were calculated, with DPN ꢃ3. It is sug-
gested that the short-stack lengths contributed to the fact that
no clear expression of the molecular chirality was found in
either the poorly defined solid-state aggregates or in the ob-
served mesophase structures. The solvent processibility of
these materials, in combination with the ability to induce chir-
ality into the supramolecular structures formed in solution
makes these PDIs highly desirable candidates for the prepara-
tion of complex anisotropic materials by ionic self-assembly.
Perylene tetracarboxylic dianhydride (44 mg, 0.112 mmol) and N,N’-
dimethylamino-3-phenylpropanamine (100 mg, 0.56 mmol) were
dissolved in butan-1ol (8 mL). This mixture was heated to 908C
under nitrogen for 24 h. TLC analysis indicated a reaction had oc-
curred. (CHCl3/BuOH 10:1, triethylamine). The solvent was removed
by evaporation under reduced pressure, and the product washed
with stirring in NaOH (aq) (5% w/v) for 30 m at 908C. The solid
product was obtained by centrifugation, then washed with stirring
in a EtOH/water solvent (3:1 w/v). The product was obtained by
centrifugation and dried under vacuum and used without further
purification. Yield: 61 mg, 76.5%; 1H NMR (300 MHz, CDCl3): d=
8.6–8.53 (m, 8H, HPERY), 7.26–7.00 (m, 10H, HPHE), 4.46 (dd, 2H, J=
13.3, 8.6 Hz, C(1)H2a), 4.14 (dd, 2H, J=13.3, 6.3 Hz, C(1)H2b,), 3.67–
3.62 (m, 2H, C(2)H), 3.09 (dd, 2H, J=14.0, 4.6 Hz, C(3)H2a), 2.60 (dd,
2H, J=14.0, 9.2 Hz, C(3)H2b), 2.44 ppm (s, 12H, CH3); MS (ESI+): m/
z: 713.1 [M+H]+
General Procedure for the synthesis of N,N’-bis[2-(trimethyl-
ammonium)-3-(phenyl)propyl]perylene diimide
Experimental Section
Materials and methods
N,N-Bis[2-(dimethylamino)-3-(phenyl)propyl]perylene
diimide
1H NMR spectra were recorded on JEOL spectrometers
(Lambda 300 and Eclipse 400 at 300 and 400 MHz, respectively)
and referenced to deuterated solvents. CD measurements were ob-
tained with a JASCO-J815 spectropolarimeter fitted with a Peltier
temperature controller. UV/Vis data was recorded using a Perki-
nElmer Lambda 35 UV/Vis spectrometer in the range 200–800 nm
with a Peltier temperature controller. For UV and CD spectra re-
corded with temperature, heating was carried out at a rate of
(BDPPP, 30 mg, 0.042 mmol) was dissolved in DMF (2 mL) and
methyl iodide (0.262 mL, 4.2 mmol) was added. Additional DMF
(2 mL) was added and the mixture was stirred under an inert nitro-
gen atmosphere at 308C for 24 h, then at RT for a further 12 h. TLC
analysis was used to monitor the reaction progress (CHCl3/EtOH,
triethylamine 10:3). The solvent was removed by evaporation at re-
duced pressure to give the product, a dark purple solid. The prod-
uct was washed with stirring in chloroform (50 mL) for 1 h. The
bright pink solvent was removed by decantation and the solid
sample dried under vacuum. Yield: 26.8 mg, 64%; 1H NMR
(300 MHz, CD3CN): d=8.64–8.39 (m, 8H, HPERY), 7.12–6.66 (m, 10H,
HPHE), 4.83 (dd, 2H, J=13.3, 8.5 Hz, C(1)H2a), 4.54 (dd, 2H, J=13.3,
4.7 Hz, C(1)H2b), 4.50–4.42 (brm, 2H, C(2)H), 3.51–3.44 (brm, 2H,
608Chrꢀ1
. Fluorescence measurements were obtained using
a Varian Cary spectrophotometer at an excitation wavelength of
l=470 nm in the range l=500–800 nm. Due to the high-emission
intensity of samples, slit widths of l=2.5 and 5 nm was used for
MeOH and aqueous solutions respectively. All spectra were ob-
Chem. Eur. J. 2015, 21, 1 – 12
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