CHEN ET AL.
3
1
3
Chemical Co, Ltd (Chengdu, China). All of the reagents
involved in this study were of analytical grade or above.
The methanol used in HPLC analysis was of HPLC grade,
and water used in this work was ultrapure grade.
(m, 2H). C NMR (101 MHz, D O) δ177.08, 128.17,
2
122.76, 119.32, 109.14, 100.00, 61.26, 49.58, 32.18, 31.03,
29.52, 24.16, 18.68, 12.56.
1
[ViImC ][L‐Pro]: H NMR (400 MHz, D O) δ7.75 (d,
5
2
1
1
H), 7.43 (d, 1H), 7.14 to 7.08 (m, 1H), 5.79 to 5.74 (m,
H), 5.41 to 5.38 (m, 1H), 4.21 to 4.18 (m, 2H), 3.79 to
2
2
.2 | Preparation of L‐Phe@MIPs
3.76 (m, 1H), 3.19 to 3.17 (m, 1H), 3.03 to 3.00 (m, 1H),
.21 to 2.17 (m, 1H), 1.86 to 1.75 (m, 6H), 1.35 to 1.32
2
13
.2.1 | Synthesis and characterization of
(m, 2H). C NMR (101 MHz, D
O) δ176.86, 128.16,
2
[ViImCn][L‐Pro]
122.76, 119.33, 109.16, 100.01, 61.25, 49.85, 31.06, 29.47,
2
8.70, 27.44, 24.12, 21.32, 13.04.
1
The synthesis of [ViImC ][Br] (n = 3, 4, 5, 6) (Scheme 1):
[ViImC ][L‐Pro]: H NMR (400 MHz, D O) δ7.77 (d,
n
6
2
A certain amount of CH (CH ) Br and N‐vinylimidazole
1H), 7.58 (d, 1H), 7.17 to 7.11 (m, 1H), 5.82 to 5.77 (m,
1H), 5.43 to 5.41 (m, 1H), 4.22 to 4.18 (m, 2H), 3.81 to
3.71 (m, 1H), 3.27 to 3.20 (m, 1H), 3.04 to 3.00 (m, 1H),
2.21 to 2.20 (m, 1H), 1.92 to 1.81 (m, 6H), 0.94 to 0.90
3
2 n
was placed in a 100‐mL round‐bottom flask equipped
with a magnetic stirrer, and an appropriate amount of
acetonitrile was added as solvent. Then, the reaction mix-
ture was heated to reflux for 24 hours under stirring.
After that, the solvent was removed under vacuum, and
the product was washed with ethyl acetate and acetone
one to two times. Finally, the product was dried for
13
(m, 4H). C NMR (101 MHz, D O) δ177.48, 128.15,
2
122.78, 119.34, 109.18, 100.01, 61.28, 49.87, 31.75, 30.25,
29.62, 28.94, 24.91, 24.24, 21.70, 13.17.
2
4 hours under high vacuum at T = 353.15 K.
The synthesis of [ViImC ][OH] (n = 3, 4, 5, 6): After
n
[
ViImC ][Br] is dissolved with a small amount of water,
2.2.2 | Preparation of L‐Phe@MIPs
n
the solution was poured into a column packed with
01x7 type strong basic anion exchange resins for
21-23
2
Similar to the normal synthesis method,
using ionic
exchange reaction. The aqueous solution of silver nitrate
was used to monitor the process of the reaction.
liquids as functional monomers and a cross‐linking agent
to bond a subimprinted polymer was applied. In this
experiment, after 912 mg of ILs is dissolved in 6 mL of
water and 30 mL of methanol in a 100‐mL round‐bottom
The synthesis of [ViImC ][L‐Pro]: A slight excess of
n
L‐Pro was added to the [ViImC ][OH] solution, and the
n
reaction mixture was stirred at room temperature for
flask, 200 mg of Cu(Ac) and 75.0 mg of L‐Phe were
2
2
4 hours. Then, the solvent was distilled off under reduced
added under stirring. And then, the mixture was soni-
pressure to obtain a wine‐red viscous oily substance. The
cated for 15 minutes and allowed to stand overnight at
2+
product [ViImC ][L‐Pro] was stored in a dry environment
60°C to make the ionic liquid monomers, Cu , and L‐
Phe fully interact to form a prepolymerized solution.
Afterwards, 1.8 g of MBA was added, and the mixture
was purged with pure nitrogen for 20 minutes. Then, it
was allowed to stand for 2 to 3 hours in room tempera-
ture, and 50 mg of AIBN was added. The initiator was
uniformly dispersed under a nitrogen atmosphere for
10 minutes, and the solution was heated to react at
60°C for 24 hours. The products were centrifuged, and
the resulting solid needed to be grinded, screened, and
eluted with methanol/acetic acid (8:2, v/v) until no tem-
plate could be detected in the washing solution. Then,
the products were dried in a vacuum drying oven at
60°C to obtain imprinted polymer particles L‐Phe@MIPs.
n
1
13
with low temperature for further use. The H and
C
nuclear magnetic resonance (NMR) spectra of [ViImCn]
[
L‐Pro] were shown in supporting information (Data S1).
1
[
ViImC ][L‐Pro]: H NMR (400 MHz, D O) δ7.76 (d,
3
2
1
1
3
2
H), 7.55 (d, 1H), 7.14 to 7.08 (m, 1H), 5.80 to 5.75 (m,
H), 5.42 to 5.39 (m, 1H), 4.27 to 4.22 (m, 2H), 3.83 to
.81 (m, 1H), 3.21 to 3.20 (m, 1H), 3.05 to 3.03 (m, 1H),
13
.22 to 2.18 (m, 1H), 1.88 to 1.81 (m, 4H). C NMR
(
101 MHz, D O) δ177.08, 128.17, 122.76, 119.32, 109.14,
2
1
00.00, 61.26, 49.58, 31.03, 29.52, 24.16, 18.68, 12.56.
1
[
ViImC ][L‐Pro]: H NMR (400 MHz, D O) δ7.75 (d,
4
2
1
1
3
2
H), 7.44 (d, 1H), 7.12 to 7.08 (m,1H), 5.79 to 5.73 (m,
H), 5.41 to 5.39 (m, 1H), 4.24 to 4.20 (m, 2H), 3.75 to
.61 (m, 1H), 3.32 to 3.17 (m, 1H), 3.02 to 3.00 (m, 1H),
.21 to 2.14 (m, 1H), 1.88 to 1.74 (m, 4H), 1.35 to 1.14
The synthesis of the L‐Phe@MIPs was similar to the L‐
1
2+
Phe@MIPs except that no Cu was used. As a control,
SCHEME 1 The synthetic procedure of
ViImC ][L‐Pro]
[
n