Substitution effect of super hydrophobic units: A new strategy to design deep blue fluorescent emitters

Article abstract of DOI:10.1016/j.dyepig.2016.12.034

Fluorescent deep-blue emitters consisting of arylamine chrysene have attracted immense commercial interest in organic light-emitting devices (OLEDs). Herein, we endeavor to design emitters with super hydrophobic groups, namely trifluoromethoxy ([sbnd]OCF<

Full text of DOI:10.1016/j.dyepig.2016.12.034

Accepted Manuscript
Substitution effect of super hydrophobic units: A new strategy to design deep blue
fluorescent emitters
Ke Li, Shuai Yang, Yantong Chen, Yaowu He, Imran Murtaza, Osamu Goto, Clifton
Shen, Gufeng He, Hong Meng
PII:
S0143-7208(16)31050-6
10.1016/j.dyepig.2016.12.034
DYPI 5659
DOI:
Reference:
To appear in: Dyes and Pigments
Received Date: 25 October 2016
Revised Date: 15 December 2016
Accepted Date: 15 December 2016
Please cite this article as: Li K, Yang S, Chen Y, He Y, Murtaza I, Goto O, Shen C, He G, Meng H,
Substitution effect of super hydrophobic units: A new strategy to design deep blue fluorescent emitters,
Dyes and Pigments (2017), doi: 10.1016/j.dyepig.2016.12.034.
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ACCEPTED MANUSCRIPT
Table of Content

ACCEPTED MANUSCRIPT
Substitution Effect of Super Hydrophobic Units: A New Strategy to design Deep Blue
Fluorescent Emitters
a
b
a
a
c
a
a
b
a
Ke Li, Shuai Yang, Yantong Chen, Yaowu He, Imran Murtaza, Osamu Goto, Clifton Shen, Gufeng He* and Hong Meng*
a
School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen, 518055, China.
b
Center for Opto-electronic Materials and Devices, Dept of Electronic Engineering, Shanghai Jiao Tong University, National
Engineering Lab for TFT-LCD Materials and Technologies, 800 DongChuan Rd, Shanghai 200240, China.
Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation
c
Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, China.
Abstract: Fluorescent deep-blue emitters consisting of arylamine chrysene have attracted immense commercial interest in organic light-
emitting devices (OLEDs). Herein, we endeavor to design emitters with super hydrophobic groups, namely trifluoromethoxy (-OCF ) or
3
trifluoromethylsufanyl (-SCF ) substituted on 6,12-diarylamine chrysene. Surprisingly, the new materials show highly efficient and
3
substantial blue shift in fluorescence spectra with more pure color quality, higher thermostability and better moisture resistant properties.
Astonishing electroluminescence performance is envisioned by promoting the molecular design based on experience and theoretical
calculations along with the single crystal X-Ray analysis. The CIE coordinate values for 6, 12-diamine-N,N,N’,N’-tetra(p-
trifluoromethoxyphenyl)chrysene (DATPC-OCF ) and 6,12-diamine-N,N,N’,N’-tetra(p-trifluoromethylsulfanylphenyl)chrysene (DATPC-SCF )
3
3
are (0.14, 0.09) and (0.15, 0.06), respectively, which exactly match with the National Television System Committee (NTSC) and High-
Definition Television requirements for unprecedented deep-blue emission.
Keywords: Deep Blue; Intermolecular Packing; Material Chemistry; OLED; Photoluminescence; Super Hydrophobic
resistant molecules with intrinsic hydrophobic properties will be
1
. Introduction
beneficial for the stability of the OLEDs.[13] Considering the above
issues, we strategically introduce super hydrophobic groups
substitution to realize highly efficient deep blue luminance.
Trifluoromethoxy (-OCF3) or trifluoromethylsufanyl (-SCF3)
groups, because of their super hydrophobic property have been
remarkably used in agrochemicals, medical imaging and
pharmaceuticals,[14] owing to their high Hansch hydrophobicity
Since Tang et al first demonstrated a multilayer device structure
to achieve high efficiency in 1987,[1] organic light-emitting diodes
OLEDs) have been the most promising technology for the third
(
generation displays.[2] However, pure blue emitter with high
luminous efficiency (4-5 cd/A) and suitable Commission
Internationale de L’Eclairage (CIE) coordinates of (0.12-0.15, 0.06-
parameter (π ) of 1.04 and 1.44, respectively (compared to
0
.10) are still challenging.[3, 4] Therefore, it is highly desirable to
R
trifluoromethyl group with π = 0.88). Moreover, a relatively small
obtain a stable and high-performance blue emitter to make OLEDs
with three primary colors. Although thermally activated delayed
fluorescence (TADF) and phosphorescent OLEDs have recently
obtained higher efficiency, fluorescent emitters are more
competitive because of the more credible device performance and
easier fabrication.[5] At present, only conventional fluorescent
emitters have managed to realize large scale industrial production.
High efficiency roll-off at high luminance and shorter lifetime are
inherent drawbacks of TADF and phosphorescent OLEDs.[6]
Fluorescent deep-blue emitters, arylamine substituted chrysene[7],
are so far reported to be the best blue dopant material in OLEDs.[8,
R
overlap integral between the adjacent molecules is needed to
realize fluorescent blue emission.[15] According to the equation,
ꢁ
ꢂꢃꢄ
E
ꢀ
(eV) =
, if we want to obtain a deep blue coloured emitter,
ꢅ(ꢆꢇ)
the bandgap should be increased. In other words, one useful
strategy to get deep blue fluorescence is to introduce strong
electron withdrawing groups to redistribute active electron
density,[16, 17] or bulky substituents to obtain steric separation.
The matter of rejoice is that -OCF3 and -SCF3 are also strong
electron withdrawing groups.[18] Recently, the Jongwook Park
group designed deep blue fluorescent emitters using the
triphenylamine substituted chrysene achieving impressive high
EQE.[8] However, 6,12-bis(triphenylamine)chrysene hardly makes
any blue shift in luminescence spectra as compared to 6,12-
diarylamine chrysene (DATPC). It may be due to the fact that
arylamine groups do not efficiently distribute active electron
density[19]. So we envisage that introducing -OCF and -SCF super
9
] However, blue fluorescence emitters have external quantum
efficiency (EQE) almost below 3%,[10] low color purity and unstable
lifetime, which are urgent problems to solve in all blue OLEDs.[11]
Our work focuses on the design and development of an emitting
material, comprising the prominent class of chrysene, to achieve
tuned deep-blue color emission. In particular, we endeavor to
accomplish novel high efficient deep blue emitters with super
moisture resistant characteristics. Although tuning deep blue
emission of the chrysene chromophores has been demonstrated
through various substituted groups, only a little research work has
been conducted to address the stability of emitting materials. It is
widely accepted that one of the degradation pathways of OLEDs is
electrochemical oxidation and reduction processes,[12] most likely
due to the oxygen and water effects. Thus, designing moisture
3
3
hydrophobic and strong electron withdrawing groups can realize
fluorescence emission sustaining blue shift and enhance the
stability synergistically.
Herein, we demonstrate novel DATPC derivatives with para-
substituted -OCF3 and -SCF3 groups in phenyl rings. Molecular
structures
of
DATPC,
6,12-diamine-N,N,N’,N’-tetra(p-
trifluoromethoxyphenyl)chrysene (DATPC-OCF ) and 6,12-diamine-
3
N,N,N’,N’-tetra(p-trifluoromethylsulfanylphenyl)chrysene (DATPC-
SCF ) are illustrated in Scheme 1 and their synthesis techniques are
3
summarized in Scheme 2. The Density Functional Theory (DFT)
*
Corresponding authors.
E-mail addresses: menghong@pkusz.edu.cn (Hong Meng) and
gufenghe@sjtu.edu.cn (Gufeng He)
calculation along with the single crystal X-ray analysis establish the

correctness of design strategy. DATPC-OCF an
substantial blue shift in UV-vis absorption and fluorescence spectra.
A
d D
C
A
C
TP
E
C-S
P
C
T
F
E
sh
D
owMAThe
N
or
U
et
S
ica
C
l c
R
alc
I
ulations, the single crystal X-Ray analysis, physical
P
T
3
3
and optical properties
Scheme 1 Structures of DATPC, DATPC-OCF and DATPC-SCF .
3
3
Figure 1. Molecular structure; HOMO and LUMO electron density
and orbital energy level at S state calculated by the DFT B3LYP/6-
0
3
1G* for DATPC, DATPC-OCF and DATPC-SCF .
3 3
DFT calculations (B3LYP/6-31G* as basis set) of the DATPC
complexes were carried out to evaluate the effect of -OCF and -
3
SCF substitution and the results are summarized in Figure 1 and
3
Table 1. As shown in Figure 1, -OCF and -SCF substituent groups
3
3
withdraw the HOMO electron to diphenylamine group, separating
them from the LUMO electron concentrate on chrysene core. The
theoretically predicted and experimental values of the bandgap (Eg)
of DATPC are 3.4 eV and 2.81 eV, respectively. Actually, DATPC has
ꢁ
ꢂꢃꢄ
sky blue-colored emission and according to E (eV) =
, if one
ꢀ
ꢅ(ꢆꢇ)
wants to get a deep blue color emitter, the bandgap of new
molecules should be wider than that of DATPC. Further comparison
of the theoretical and experimental values of bandgaps of DATPC,
DATPC-OCF and DATPC-SCF in Table 1, reveals that the values of
3
3
their bandgaps follow the order: DATPC＜DATPC-OCF ＜DATPC-
3
SCF . It indicates fluorescence emission sustaining blue shift from
3
DATPC to DATPC-SCF . Oxygen and sulfur atoms possess two
3
additional pairs of non-bonding electrons[20], which lowers the
HOMO more than the LUMO, it may be the net effect which causes
the bandgap to increase. The enlarged bandgap is also attributed to
slightly decreased intramolecular conjugation length.[21, 22] Most
importantly, –OCF and –SCF substitution is probably unique one
Scheme 2. Synthesis of 6,12-diphenylaminechrysene (DATPC) and
its derivatives (DATPC-OCF and DATPC-SCF ).
3
3
3
3
to fine-tune and engineer the bandgap in order to achieve deep
blue emission in highly efficient OLED materials.
The narrower full width at half maximum (FWHM) (49-50 nm) of
absorption and fluorescence spectra as compared to DATPC (63 nm)
imply higher color purity. Single layer undoped devices achieve
maximum external quantum efficiency (EQE) of 3.05% and the CIE
coordinate values of (0.14, 0.09) and (0.15, 0.06) for DATPC-OCF3
The crystal structures of DATPC-OCF and DATPC-SCF are shown
3
3
in Figure 2 (a) and (b). Whereas for DATPC, it proved to be
unfeasible to obtain the single crystal due to its instability. From
single crystal X-ray structures, the corresponding dihedral angles
and DATPC-SCF , respectively, which exactly meet the High-
3
between chrysene and phenyl groups of DATPC-OCF and DATPC-
Definition Television ITU-R BT.709 requirement of CIE (0.15, 0.06)
for deep-blue emission[11]. Based on the aforementioned facts, we
report a simple fabrication process to obtain deep-blue and highly
efficient novel emitters for OLEDs by incorporating super
hydrophobic units of -OCF or -SCF substituted in 6,12-diarylamine
3
o
o
SCF are 87.61 and 89.43 , which are almost equal to right-angle.
3
The DFT calculation shows that the torsion angles for DATPC,
o
o
o
DATPC-OCF3 and DATPC-SCF3 are 77.77 , 85.04 and 87.54 ,
respectively, which are in good agreement and confirm the same
3
3
chrysene.
3
order with the single crystal data. Thus, the bulky -OCF and -SCF3
substituents coincide with the former idea of steric separation to
realize high efficiency. Figure 2 (c), (d) and (e) are the optimized
2
. Results and discussion
dimer aggregation structures of DATPC, DATPC-OCF and DATPC-
3

SCF3 by Spartan molecular modeling method
overlap integrals of all the three dimers are very low and nearly no
A
.
C
Th
C
e
E
ag
P
gr
T
eg
E
at
D
ionMAπ-π
N
in
U
ter
S
ac
C
tio
R
n
I
is observed. Combined with the single crystal X-ray
P
T
Table 1. Physical properties of DATPC, DATPC-OCF and DATPC-SCF3
3
[
a]
DFT calculation (eV)
Experimental data (eV)
Compound
[b]
[c]
HOMO
LUMO
Bandgap
HOMO
LUMO
Bandgap
DATPC
DATPC-OCF3
DATPC-SCF3
-4.80
-5.21
-5.49
-1.40
-1.79
-1.95
3.4
3.42
3.54
-4.98
-5.28
-5.40
-2.17
-2.32
-2.38
2.81
2.96
3.02
[a]
[b]
[c]
The S states of the compounds calculated using B3LYP/6-31G* basis set. HOMO obtained from cyclic voltammetry. LUMO
0
obtained from the HOMO and the optical bandgap.
Figure 2. The single X-ray crystal structure of (a) DATPC-OCF and
3
(
b) DATPC-SCF . Molecular modeling method optimized dimer
3
structures of (c) DATPC, (d) DATPC-OCF and (e) DATPC-SCF .
3
3
highly-ordered molecular packing details of DATPC-OCF3 and Figure 3. Molecular packing structures of (a) DATPC-OCF and (b)
3
DATPC-SCF in Figure 3, it is obvious that DATPC, DATPC-OCF and
3
3
DATPC-SCF3.
DATPC-SCF all adopted J-type aggregation stacking columns.[23]
3
The overlap percentage of two adjacent chrysene planes has
gradually reduced from DATPC to DATPC-SCF3.
Figure 3 (a) and (b) are the highly-ordered molecular packing
details of DATPC-OCF3 and DATPC-SCF3 respectively. This
herringbone cross-lamination arrangement of chrysene core is
significantly beneficial to reduce transportation distance of the
percentage and avoid co-planarity with chrysene, which results in
the reduction of emission efficiency, causing bathochromic and
broad emissions[8].
The UV-vis absorption wavelengths of DATPC-OCF (383 nm) and
3
DATPC-SCF (378 nm) in their solution states are about 22-27 nm
3
blue shifted than that of DATPC (405 nm) shown in Figure 4 (a). The
fluorescence emission spectra show emission peaks at 440 nm
excitons. In the case of DATPC-OCF , the shortest intermolecular
3
distance is 3.47 Å (from hydrogen atom to fluorine atom). For
(
DATPC-OCF ) and 435 nm (DATPC-SCF ), which are 37-42 nm blue
3 3
DATPC-SCF , the shortest distance between two adjacent molecules
3
shifted than that of DATPC (477 nm). FWHM values of the
is 2.55 Å (from hydrogen atom to fluorine atom). In fact, these
shorter distances promote intermolecular exciton transfer. The
intermolecular chrysene-chrysene distances obtained from single X-
ray crystal data of DATPC-OCF and DATPC-SCF are 3.434 Å and
fluorescence emission are 51 nm and 48 nm for DATPC-OCF and
3
DATPC-SCF , respectively, which are over 12 nm narrower as
3
compared to that of DATPC (63 nm). Photoluminescence quantum
yield (PLQY) in solution state of DATPC-OCF and DATPC-SCF are
3
3
3
3
3
.330 Å, respectively, where it is generally accepted that high-
5
0% and 42%, respectively, while that of DATPC is 47%, for details
efficient intermolecular interaction often occurs within effective
distance smaller than 4.0 Å.[23, 24] The head-to-head aggregation
subserves the exciton transfer between adjacent molecules to
promote blue emission and prevents exciton quenching. In
conclusion, -OCF and -SCF substituents decrease the packing
in Figure S1 (ESI†). Figure 4 (b) summarizes the UV-vis absorption
and fluorescence emission spectra in solid state, with the same
changing tendency as that of the solution state. The optical
properties are listed in Table 2. The cyclic voltammetry (CV) are
3
3
summarized in Figure S2 (ESI†). In conclusion, -OCF and -SCF3
3
Table 2 Optical and thermal properties of DATPC, DATPC-OCF , and DATPC-SCF
3
3
[a]
[b]
In Solution
On Film
[
c]
o
o
o
Compound
UV
nm)
PL
(nm)
FWHM
(nm)
UV
(nm)
PL
(nm)
FWHM
(nm)
PLQY (%)
T (C )
T (C )
T (C )
g
m
d
(
DATPC
DATPC-OCF3
DATPC-SCF3
405
383
378
477
440
435
62.96
50.79
47.46
397
385
380
450
438
433
63.21
51.10
48.91
47
50
42
-
95
112
-
332
335
378
237
277

ACCEPTED MANUSCRIPT
[a]
-5
[b]
[c]
1
×10 M in anhydrous chloroform. Film thickness is 50 nm on the glass. The solution-state in anhydrous chloroform relative quantum
yield using the 2-Aminopyridine in 0.1M H SO as the reference.
2
4
Figure 5. Contact angles of (a) DATPC, (b) DATPC-OCF , and (c)
3
DATPC-SCF3 measured by 2 µL water spread over vacuum-
deposited 50 nm films on the glass.
Electroluminescence properties
Although certain doped fluorescent OLEDs, which have been
reported so far, can realize higher efficiency, undoped OLEDs are
more attractive due to stable device performance and simple
manufacturing processes.[5] Subsequently, blue undoped OLEDs
with the structure [ITO/MoO3 (1 nm)/TCTA (60 nm)/DATPC
derivative (20 nm)/TPBi (40 nm)/LiF (1 nm)/Al (200 nm)] were
fabricated. The optical and physical properties of the resulting
devices are summarized in Figure 6 and Table 3.
The EL spectra of DATPC derivative-based OLEDs are shown in
Figure 6 (a). The excimer emission peaks from new DATPC-OCF3
(
435 nm) and DATPC-SCF (430nm) are 25-30 nm shorter than that
3
of DATPC (460 nm). FWHM value of DATPC-OCF3 (49 nm) and
DATPC-SCF (50 nm) is 16 nm narrower than that of DATPC (66 nm).
3
The EL spectra of DATPC-OCF and DATPC-SCF based OLED devices
3
3
shows better blue color luminance and higher color purity. The
EQE-current density curves of the devices are shown in Figure 6 (b).
The maximum EQE of DATPC-OCF and DATPC-SCF is obtained to
3
3
be 2.70% and 3.05%, respectively, which is
a significant
improvement over that of DATPC (2.06%). Although EQE of DATPC-
SCF is highest, it gets roll-off quickly with the increase in current
3
Figure 4. The UV-vis absorption (solid dots) and fluorescence
density. In general, the possible reason may be the difference in
electron and hole mobility[27] as the material’s energy barriers of
hole-transporting and electron-transporting layer do not match
very well. To further investigate this issue from the aspect of the
concentration quenching effect, the time-resolved emission spectra
were also recorded in Figure S5 (ESI†) and Table S1 (ESI†). DATPC,
(
hollow dots) spectra of DATPC, DATPC-OCF and DATPC-SCF (a) in
3
3
-5
anhydrous chloroform solution (1×10 M); (b) in the vacuum-
deposited films (50 nm) on glass substrates.
substituent modification can provide deep blue emission as well as
higher color purity. The differential scanning calorimetry (DSC) in
Figure S3 (ESI†) and thermogravimetric analysis (TGA) in Figure S4 DATPC-OCF
and DATPC-SCF show exciton lifetimes of 3.7 ns, 3.4
3
3
(
ESI†) were carried out to evaluate the thermal properties of our ns and 2.0 ns, respectively, in solution state. The longer exciton
new materials and are summarized in Table 2. From the thermal lifetime can provide enough time for its transportation and
3
property data, it is suggested that the additional –OCF and –SCF3
aggregation in emitting layer, significantly for blue conventional
substituents can improve thermostability of the corresponding
fluorescence materials.[28] Figure 6 (c) exhibits the CIE coordinate
compounds, that may otherwise attribute to the unstable arylamine
structure.[25, 26]
values for DATPC(0.17, 0.20), DATPC-OCF (0.14, 0.09) and DATPC-
3
SCF (0.15, 0.06). It is noteworthy that we have unprecedentedly
3
designed deep-blue emitters meeting the requirements of
television displays with CIE coordinates of (0.14, 0.08) regulated by
To study the effect of substituents on the hydrophobic property,
contact angle measurements were also carried out and listed in
Figure 5. The contact angles of DATPC, DATPC-OCF and DATPC-
3
o
o
o
SCF are 88.563 , 103.556 and 90.000 , respectively, obtained
3
from an average value of five reasonable distribution points.
Evidently, the hydrophobic property is enhanced by -OCF and -
3
SCF substituents, providing better device stability.
3

ACCEPTED MA (C o
N
mp
U
ou
S
nd
C
3
R
[
I
b
P
is(
T
4-trifluoromethoxyphenyl)amine] : Compound 1
4-trifluoromethoxybromobenzene)
(24.10 g, 0.1 mol) and
compound 2 (4-trifluoromethoxyphenylamine) (17.71 g, 0.1 mol)
were added to dry toluene solution (300 mL). 1,1’-
Bis(diphenylphosphino)ferrocene (DPPF) (6.65 g, 12 mmol), [1,1’-
bis(diphenylphosphino)ferrocene]palladium(II)
dichloride
dichloromethane adduct [(DPPF)PdCl .CH Cl ] (0.33 g, 0.4 mmol)
2
2
2
and po+tassium tert-butoxide (KOtBu) (9.61 g, 0.1 mol) were added
to the reaction mixture under nitrogen atmosphere. The reaction
o
was stirred for 5 hours at 120 C. After completing the reaction, the
mixture was poured into water (100 mL); the organic layer was
extracted with ethyl acetate and distilled water. The obtained
organic layer was isolated by silica gel column chromatography
using the ethyl acetate : petroleum ether (1 : 9) to get the oily
1
product. Yield 67%. H NMR (300 MHz, Chloroform-d) δ 7.15 (d, J =
1
3
8
.4 Hz, 4H), 7.04 (d, J = 9.0 Hz, 4H), 5.72 (s, 1H). C NMR (126 MHz,
Chloroform-d) δ 143.65, 142.07, 122.79, 119.09.
Compound [bis(4-trifluoromethylsufanylphenyl)amine]
Figure 6. (a) Normalized EL spectra of OLED devices made of Compound 4 [4-(trifluoromethylsufanyl)bromobenzene] (21.42 g,
DATPC, DATPC-OCF3 and DATPC-SCF ; (b) External quantum 0.083
mol) and compound [4-
efficiency (EQE) versus current density; (c) CIE coordinate; (d) (trifluoromethylsufanyl)phenylamine] (19.31 g, 0.1 mol) were
6
:
3
5
Device structure of DATPC and its derivatives as blue emitters.
added
Bis(diphenylphosphino)ferrocene (DPPF) (6.65 g, 12 mmol), [1,1’-
bis(diphenylphosphino)ferrocene]palladium(II) dichloride
dichloromethane adduct [(DPPF)PdCl .CH Cl ] (0.33 g, 0.4 mmol)
to
dry
toluene
solution
(300
mL).
1,1’-
the National Television System Committee (NTSC); and High-
Definition Television ITU-RBT.709 requiring CIE of (0.15, 0.06) for
2
2
2
and potassium tert-butoxide (KOtBu) (9.61 g, 0.1 mol) were added
deep-blue emission.[11] Figure 6 (d) shows OLED device structure to the reaction mixture under nitrogen atmosphere. The reaction
o
incorporating DATPC, DATPC-OCF or DATPC-SCF as active emission was stirred for 5 hours at 120 C. After completing the reaction, the
3
3
layer. Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) was applied as hole- mixture was poured into water (100 mL); the organic layer was
extracted with ethyl acetate and distilled water. The obtained
transporting and exciton-blocking layer and 1,3,5-Tris(N-
organic layer was isolated by silica gel column chromatography
phenylbenzimidazol-2- yl)benzene (TPBi) was utilized as electron-
using the ethyl acetate : petroleum ether (1 : 9) to get the oily
transporting and exciton- blocking layer. In this article, we mainly
1
product. Yield 73%. H NMR (300 MHz, Chloroform-d) δ 7.57 (d, J =
focused on the innovation in material structure, and not too much
on the exploration of device structure. But we believe that the roll-
off problem of our new materials can be solved with a subsequent
study to design appropriate device structure.
13
8
.6 Hz, 4H), 7.13 (d, J = 8.7 Hz, 4H), 6.08 (s, 1H). C NMR (126 MHz,
Chloroform-d) δ 144.82, 138.53, 115.83, 60.84 .
Compound 9 (DATPC): Compound 7 (6,12-dibromochrysene) (1.94 g,
5
mmol) and compound 8 (4.49 g, 20 mmol) were added to dry
toluene solution (120 mL). Tris(dibenzylideneacetone)dipalladium(0)
Table 3 Electroluminescence efficiency of DATPC, DATPC-OCF and
3
[Pd (dba) ] (0.092 g, 0.1 mmol), tri-tert-butylphosphonium
2
3
-
2
DATPC-SCF at 5 mA cm
3
tetrafluoroborate [P(tBu) HBF ] (0.029 g, 0.2 mmol) and potassium
3 4
tert-butoxide (KOtBu) (1.68 g, 1.5 mmol) were added to the
EL
b
CIE
ELmax
(nm)
a
CE (cd
reaction mixture under nitrogen atmosphere. The reaction was
Compound
FWHM
V (V)
-1
A )
EQEmax
o
stirred for 5 hours at 110 C. After completing the reaction, the
(
x,y)
(
nm)
mixture was poured into water (50 mL); the organic layer was
extracted with dichloromethane and distilled water. The obtained
organic layer was isolated by silica gel column chromatography
(
0.17,
DATPC
460
65.44
48.75
49.69
4.7
5.5
5.8
2.62
1.71
1.05
2.06
2.70
3.05
0
.20)
1
using the dichloromethane : petroleum ether (1:3). Yield 19%. H
DATPC-
OCF3
(0.14,
0.09)
NMR (300 MHz, Chloroform-d) δ=8.55 (d, J = 8.8 Hz, 4H), 8.11 (d, J =
8.3 Hz, 2H), 7.59 (t, J = 7.6 Hz, 2H), 7.47 (t, J = 7.5 Hz, 2H), 7.21 (d, J
4
4
35
30
1
3
=
7.6 Hz, 8H), 7.15 (d, J = 8.0 Hz, 8H), 6.96 (t, J = 7.2 Hz, 4H).
NMR (126 MHz, Chloroform-d) δ 129.21, 129.18, 129.10, 126.96,
26.90, 126.85, 125.07, 124.99, 123.62, 121.95, 121.86, 121.77.
C
DATPC-
SCF3
a
(0.15,
0.06)
1
b
+
Operating voltage. Current efficiency
HRMS(APCI): m/z calcd for C H N [M+H] 563.2482; found
42 31 2
5
63.2476.
Compound 10 (DATPC-OCF ) : Compound 7 (5.32 g, 13.71 mmol)
3
and compound 3 (10.17 g, 30.20 mmol) were added to dry toluene
solution (150 mL). Tris(dibenzylideneacetone)dipalladium(0)
[Pd (dba) ] (0.25 g, 0.27 mmol), tri-tert-butylphosphonium
3
. Experimental
Synthesis
2
3
tetrafluoroborate [P(tBu) HBF ] (0.16 g, 0.55 mmol) and potassium
tert-butoxide (KOtBu) (3.78 g, 39.30 mmol) were added to the
3
4
DATPC, DATPC-OCF3 and DATPC-SCF3 were obtained from
bromochrysene according to the reported procedure.[8, 29, 30]
reaction mixture under nitrogen atmosphere. The reaction was
Compound
8 (diphenylamine) was obtained from chemical
o
stirred for 5 hours at 110 C. After completing the reaction, the
company.
mixture was poured into water (50 mL); the organic layer was

extracted with dichloromethane and distilled w
organic layer was isolated by silica gel column chromatography
using the dichloromethane : petroleum ether (1 : 3). Yield 63%. H
NMR (300 MHz, Chloroform-d) δ= 8.62 – 8.53 (m, 4H), 8.04 (dd, J =
A
at
C
er
C
. T
E
he
P
o
T
bt
E
ai
D
nedMADA
N
TP
Television ITU-R BT.709 requirement of CIE coordinates of
0.15, 0.06) for deep-blue emission. We believe the theory
U
C-
S
SC
C
F
R
,
I
r
P
es
T
pectively, exactly meeting High-Definition
3
1
(
prior to experiment, accurately predicting the material’s
properties, can promote the experience in molecular
formulation and designing.
8
8
.3, 1.3 Hz, 2H), 7.67 (ddd, J = 8.4, 6.9, 1.4 Hz, 2H), 7.54 (ddd, J =
.1, 6.9, 1.1 Hz, 2H), 7.17 – 7.05 (m, 16H). C NMR (75 MHz,
13
Chloroform-d) δ =146.63, 143.99, 142.22, 132.06, 130.17, 128.14,
27.67, 127.62, 124.75, 123.91, 122.74, 122.64, 122.40, 118.97.
1
+
HRMS(APCI): m/z calcd for C H F O N [M+H] 899.1774; found
46 27 12 4 2
Acknowledgements
8
99.0159.
Compound 11 (DATPC-SCF ) : Compound 7 (4.10 g, 10.55 mmol)
3
This work was financially supported by the Shenzhen Peacock
and compound 6 (8.57 g, 23.22 mmol) were added to dry toluene
solution (120 mL). Tris(dibenzylideneacetone)dipalladium(0)
Program (KQTD2014062714543296)
， Guangdong Key
Research Project (2014B090914003, 2015B090914002),
Shenzhen Key Laboratory of Organic Optoelectromagnetic
Functional Materials of Shenzhen Science and Technology Plan
[
Pd (dba) ] (0.19 g, 0.21 mmol), tri-tert-butylphosphonium
2 3
tetrafluoroborate [P(tBu) HBF ] (0.12 g, 0.42 mmol) and potassium
3
4
tert-butoxide (KOtBu) (3.04 g, 31.65 mmol) were added to the
(ZDSYS20140509094114164), Natural Science Foundation of
reaction mixture under nitrogen atmosphere. The reaction was
o
Guangdong Province (2014A030313800), Shenzhen Science
and Technology Research Grant (JCYJ20140509093817690,
stirred for 5 hours at 110 C. After completing the reaction, the
mixture was poured into water (50 mL); the organic layer was
extracted with dichloromethane and distilled water. The obtained JCYJ20150629144328079, JCYJ20160331095335232), Nanshan
organic layer was isolated by silica gel column chromatography Innovation Agency Grant (KC2015ZDYF0016A), National Basic
1
using the dichloromethane : petroleum ether (1 : 3). Yield 71%. H Research Program of China (973 Program, 2015CB856505),
NMR (300 MHz, Chloroform-d) δ=8.68 – 8.58 (m, 4H), 7.98 (dd, J =
Guangdong Academician Workstation (2013B090400016).
8
2
.3, 1.3 Hz, 2H), 7.69 (ddd, J = 8.4, 6.9, 1.4 Hz, 2H), 7.60 – 7.55 (m,
H), 7.55 – 7.47 (m, 8H), 7.24 – 7.14 (m, 8H). C NMR (75 MHz,
13
Chloroform-d) δ=149.31, 141.29, 137.84, 131.93, 128.29, 127.82,
27.73, 124.29, 123.83, 123.11, 121.94, 116.68. HRMS(APCI):m/z
calcd for C46H27F12N2S4 [M+H] 963.0860; found: 963.8682.
Notes and references
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[
[
[
[

ACCEPTED MANUSCRIPT
Highlights
ò Super hydrophobic groups, namely trifluoromethoxy (-OCF3) or
trifluoromethylsufanyl (-SCF ), substituted on 6,12-diarylamine chrysene were
3
synthesized and analysised the single crystal X-Ray.
ò The molecule design strategy shows highly efficient and substantial blue shift in
fluorescence spectra with purer color quality, higher thermostability and better
moisture resistant properties.
ò Astonishing electroluminescence performance is envisioned by promoting the
molecular design based on experience and theoretical calculations along with
the single crystal X-Ray analysis.
ò The CIE coordinate values for new materials are exactly match with the
High-Definition Television requirements for unprecedented deep-blue emission