C. Zheng et al.
Dyes and Pigments 188 (2021) 109159
Fig. 8. Endurance characteristics cycles of OFET memory devices. The writing, reading, and erasing voltages were at VGS = ꢀ 30 V, ꢀ 10 V, and 0 V (Light),
respectively: (a) Pyridyl-C device; (b) Pyridyl-N device and (c) Pyridyl-O device. Retention characteristics of OFET memory devices: (d) Pyridyl-C device; (e) Pyridyl-
N device and (f) Pyridyl-O device.
tetramethyldisiloxane (in xylene, Pt ~2%) (Karstedt’s catalyst), trie-
thoxysilane (97%), isopropylmagnesium chloride complex (i-PrMgCl-
LiCl, 1.3 M THF solution), 3-pyridyl bromide (98%), allyl bromide
(98%), potassium phosphate (98%) and 3-hydroxypyridine (99%) were
purchased from Energy Chemical. L-proline and copper(I) iodide
(99.5%) were purchased from Sinopharm Chemical Reagent Co., Ltd.
Allylamine (98%) was purchased from Xiya Reagent. All of them were
used without any further purification. Nuclear magnetic resonance
(NMR) (500 MHz) spectra were recorded on Bruker AMX400 spec-
trometer in CDCl3. HRMS-(ESI-TOF) was measured on AGILENT
1260–6230 TOF LC-MS. UV/vis spectra were recorded on Shimadzu UV-
1750. The surface morphology of pentacene was investigated by using
an XE-70 atomic force microscope (AFM) operating in tapping mode.
The electrical characteristics of the memory devices were characterized
by keithely 4200 semiconductor parameter analyzer.
triethoxysilane (4 mmol) and 2.0 mg of Karstedt’s catalyst were added in
the absence of solvent under nitrogen and then the resulting mixture was
placed at 80 ◦C for 20 h [29,30]. After cooling down to room temper-
ature, the crude product was purified by column chromatography on
silica gel with petroleum ether/ethyl acetate (3:1, v/v) as the eluent. The
collected yellow oil was concentrated to get the product (283 mg, 50%
yield). 1H NMR (500 MHz, CDCl3): δ 8.43 (m, 2H), 7.49 (m, 1H), 7.19
(m, 1H), 3.80 (q, J = 6.7 Hz, 6H), 2.64 (t, J = 7.5 Hz, 2H), 1.74 (m, 2H),
1.21 (t, J = 5.0 Hz, 9H), 0.65 (m, 2H). 13C NMR (126 MHz, CDCl3): δ
150.13, 147.31, 137.72, 136.14, 123.38, 58.53, 36.22, 24.73, 18.43,
10.25. HRMS-(ESI-TOF) for
284.16765, found: 284.17035.
C
14H25NO3Si [M+H]+: calculated:
4.2.3. N-allylpyridin-3-amine
According to the literature [31], to a 25 mL two-necked round bot-
tom flask, 1.57 g of 3-pyridyl bromide (10 mmol), 1.71 g of allylamine
(30 mmol), 4.24 g of K3PO4 (20 mmol), 0.19 g of CuI (1 mmol) and 0.23
g of L-proline (2 mmol) in dry DMF (10 mL) were added under nitrogen.
4.2. Synthetic procedures
◦
The mixture was stirred for 40 h under 80 C. After cooling down to
4.2.1. 3-Allylpyridine
room temperature, the resulting mixture was extracted with ethyl ace-
tate and water. The combined organic layers were dried over anhydrous
MgSO4 and filtrated, with the solvent being removed under reduced
pressure. The crude product was purified by column chromatography on
silica gel with petroleum ether/ethyl acetate (1:1, v/v) as the eluent. The
collected yellow oil was concentrated to get the product (1.07 g, 80%
yield). 1H NMR (500 MHz, CDCl3): δ 8.01 (m, 2H), 7.08 (m, 1H), 6.88
(m, 1H), 5.92 (m, 1H), 5.24 (m, 2H), 3.89 (s, 1H), 3.80 (m, 2H). 13C NMR
(126 MHz, CDCl3): δ 144.26, 138.56, 136.15, 134.66, 123.88, 118.59,
116.63, 46.05.
According to the literature [28], to a 25 mL two-necked round bot-
tom flask, 1.57 g of 3-pyridyl bromide (10 mmol) in dry THF (10 mL)
and 15 mL of i-PrMgCl-LiCl were added dropwise under nitrogen at 0 ◦C.
The mixture was stirred for 6 h under 0 ◦C and 4.76 g of allyl bromide
(40 mmol) was added. After the mixture was slowly warmed to room
temperature and kept stirring for 15 h, saturated NH4Cl was added and
the resulting mixture was extracted with ethyl acetate. The combined
organic layers were dried over anhydrous MgSO4 and filtrated, and the
solvent was removed under reduced pressure. The crude product was
purified by column chromatography on silica gel with petroleum
ether/ethyl acetate (1:1, v/v) as the eluent. The collected yellow oil was
concentrated to get the product (590 mg, 49.6% yield). 1H NMR (500
MHz, CDCl3): δ 8.45 (m, 2H), 7.50 (m, 1H), 7.22 (m, 1H), 5.94 (m, 1H),
5.11 (m, 2H), 3.38 (d, J = 5.0 Hz, 2H). 13C NMR (126 MHz, CDCl3): δ
150.11, 147.67, 136.31, 136.24, 135.49, 123.49, 116.96, 37.35.
4.2.4. N-(3-(Triethoxysilyl)propyl)pyridin-3-amine (Pyridyl-N)
To a dry schlenk flask, 268 mg of N-allylpyridin-3-amine (2 mmol),
656 mg of triethoxysilane (4 mmol) and 2.0 mg of Karstedt’s catalyst
were added in the absence of solvent under nitrogen and then the
◦
resulting mixture was placed at 80 C for 20 h. After cooling down to
room temperature, the crude product was purified by column chroma-
tography on silica gel with petroleum ether/ethyl acetate (1:1, v/v) as
4.2.2. 3-(3-(Triethoxysilyl)propyl)pyridine (Pyridyl-C)
To a dry schlenk flask, 238 mg of 3-allylpyridine (2 mmol), 656 mg of
7