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Journal of the American Chemical Society
Lin Pu: 0000-0001-8698-3228
organic layer was removed under vacuum and purification was
conducted by column chromatography on silica gel eluted
gradiently with 20-40% EtOAc in hexane to afford (S,S)-4 as a
yellow solid in 73% yield (340 mg). 1H NMR (600 MHz, CDCl3)
δ 10.57 (s, 2H), 8.57 (s, 2H), 8.04 (d, J = 8.2 Hz, 2H), 7.97 (d, J =
9.1 Hz, 2H), 7.88 (d, J = 8.1 Hz, 2H), 7.46-7.40 (m, 4H), 7.37 (dd,
J = 8.2, 6.7 Hz, 2H), 7.33-7.28 (m, 4H), 7.20 (dd, J = 8.6, 4.5 Hz,
4H), 7.04 (t, J = 7.8 Hz, 1H), 6.51 (d, J = 7.8 Hz, 2H), 5.14 (q, J =
13.7 Hz, 4H), 4.71 (d, J = 5.9 Hz, 2H), 4.62 (d, J = 5.9 Hz, 2H),
2.93 (s, 6H). 13C NMR (150 MHz, CDCl3) δ 191.27, 156.44,
154.01, 153.91, 137.27, 137.10, 133.89, 131.25, 130.56, 130.33,
130.28, 129.36, 129.23, 129.15, 128.22, 127.25, 126.93, 126.06,
125.21, 124.29, 119.52, 118.79, 114.60, 100.37, 71.50, 57.25.
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Supplementary Materials Available: Additional experimental
description and spectroscopic data.
Keywords: amino acid; enantioselectivity; fluorescence; chiral
recognition; BINOL
References
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Recognition. Chem. Rev. 2004, 104, 1687–1716. (b) Accetta, A.;
Corradini, R.; Marchelli, R. Enantioselective Sensing by
Luminescence. Top. Curr. Chem. 2011, 300, 175−216. (c)
Zhang, X.; Yin, J.; Yoon, Juyoung. Recent Advances in
Development of Chiral Fluorescent and Colorimetric Sensors.
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E. V. Recent Advances in Supramolecular Analytical Chemistry
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Synthesis and Characterization of (S,S)-2. Conc. HCl (2 mL)
and ethanol (1 mL) were added to (S,S)-4 (205 mg, 0.25 mmol) in
CHCl3 (1 mL) at rt. After heated at reflux for 6 h, the reaction
mixture was poured into H2O (10 mL) at rt and neutralized with
saturated NaHCO3 solution until no gas was evolved. It was then
extracted with EtOAc (2×20 mL) and concentrated under reduced
pressure to give the crude product in 99% yield (181 mg, yellow
solid). It was further purified by column chromatography on
silica gel eluted gradiently with 25-50% ethyl acetate in hexane
which gave (S,S)-2 in 91% yield (166 mg, yellow solid). 1H NMR
(600 MHz, CDCl3) δ 10.47 (s, 2H), 10.17 (s, 2H), 8.29 (s, 2H),
7.97-7.86 (m, 6H), 7.38-7.19 (m, 14H), 7.11 (t, J = 7.8 Hz, 1H),
6.67 (d, J = 7.7 Hz, 2H), 5.17 (m, 4H). 13C NMR (150 MHz,
CDCl3) δ 196.82, 156.69, 153.84, 153.59, 137.99, 137.86, 137.27,
133.76, 130.47, 130.31, 129.85, 129.59, 128.35, 127.65, 126.92,
125.51, 124.99, 124.44, 124.13, 122.24, 119.52, 118.68, 118.10,
115.08, 71.40. HRMS Calcd for C49H34NO6 (MH+): 732.2386,
Found: 732.2372 (TOF-MS). [α]2D3 = -109.8 (c = 1.0, CHCl3).
2. (a) James, T. D.; Sandanayake, K. R. A. S.; Shinkai, S. Chiral
Discrimination of Monosaccharides Using
a
Fluorescent
Molecular Sensor. Nature 1995, 374, 345–347. (b) Pugh, V.; Hu,
Q. -S.; Pu, L. The First Dendrimer-Based Enantioselective
Fluorescent Sensor for the Recognition of Chiral Amino
Alcohols. Angew. Chem. Int. Ed. 2000, 39, 3638–3641. (c) Lin,
J.; Hu, Q. -S.; Xu, M. -H.; Pu, L. A Practical Enantioselective
Fluorescent Sensor for Mandelic Acid. J. Am. Chem. Soc. 2002,
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Binol–Bisboronic Acid as Fluorescence Sensor for Sugar Acids.
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Synthesis and Characterization of (R,R)-2. Compound (R,R)-2,
the enantiomer of (S,S)-2, was obtained as a yellow solid in a two-
step yield of 71% by using the same procedure as described above
but starting with (R)-3. 1H NMR (600 MHz, CDCl3) δ 10.48 (s,
2H), 10.17 (s, 2H), 8.29 (s, 2H), 7.97-7.87 (m, 6H), 7.39-7.18 (m,
14H), 7.11 (t, J = 7.8 Hz, 1H), 6.67 (d, J = 7.7 Hz, 2H), 5.17 (m,
4H). 13C NMR (150 MHz, CDCl3) δ 196.81, 156.74, 153.86,
153.59, 137.98, 137.85, 137.17, 133.76, 130.45, 130.28, 129.85,
129.58, 128.34, 127.63, 126.91, 125.49, 124.98, 124.42, 124.11,
122.24, 119.47, 118.67, 118.09, 115.08, 71.48. HRMS Calcd for
C49H34NO6 (MH+): 732.2386, Found: 732.2405 (TOF-MS). [α]2D3
= +110.7 (c = 1.0, CHCl3).
3. (a) Pu, L. Enantioselective Fluorescent Sensors: A Tale of
BINOL. Acc. Chem. Res. 2012, 45, 150–163. (b) Pu, L.
Simultaneous Determination of Concentration and Enantiomeric
Composition in Fluorescent Sensing. Acc. Chem. Res. 2017, 50,
1032–1040.
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function of free amino acids. Elsevier, Amsterdam. 1962. (b)
Lubec, C. Amino Acids (Chemistry, Biology, Medicine). Escom
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Homma, H. (Eds) D-Amino Acids: A New Frontier in Amino
Acids and Protein Research - Practical Methods and Protocols.
Nova Science, New York, 2007. (b) Weatherly, C. A.; Du, S.;
Parpia, C.; Santos, P. T.; Hartman, A. L.; Armstrong, D. W. D-
Amino Acid Levels in Perfused Mouse Brain Tissue and Blood: A
Comparative Study. ACS Chem. Neurosci. 2017, 8, 1251–1261.
7. (a) List, B.; Lerner, R. A.; Barbas III, C. F. Proline-Catalyzed
Direct Asymmetric Aldol Reactions. J. Am. Chem. Soc. 2000,
122, 2395–2396. (b) MacMillan, D. W. C. The Advent and
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8. Amino acid-based chiral ligands: Micskei, K.; Patonay, T.;
Caglioti, L.; Pályi, G. Amino Acid Ligand Chirality for
Enantioselective Syntheses. Chem. Biodiversity 2010, 7, 1660-
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(a) Pagliari, S.; Corradini, R.; Galaverna, G.; Sforza, S.; Dossena,
A.; Montalti, M.; Prodi, L.; Zaccheroni, N.; Marchelli, R.
Sample Preparation for Fluorescence Measurement. Stock
solutions of 0.2 mM (S,S)-2 or (R,R)-2 in CH3CN or DMSO, 4
mM Zn(OAc)2 in H2O, and 1 – 20 mM amino acid in pH 8.8
BICINE buffer were all freshly prepared for each measurement.
The reaction mixtures were all allowed to stand at rt for 3 h
(unless otherwise noted) without nitrogen protection. Then, the
reaction mixtures were diluted to the desired concentration of 0.01
mM with CH3CN or DMSO. Fluorescence measurements were
conducted after 1 h, and finished within 30 min.
Acknowledgement
Partial supports from the National Science Foundation of US
(CHE-1565627), the Chinese National Natural Science
Foundation (Nos. 21877087, 21602164), Wuhan Institute of
Technology Scientific Research Fund (No. K201716), and Wuhan
International Scientific and Technological Cooperation Project
(No. 2017030209020257) are gratefully acknowledged. YYZ
also thanks the China Scholarship Council (No. 201608420202).
ORCID
Yuan-Yuan Zhu: 0000-0003-4526-5048
Shuang-Xi Gu: 0000-0003-0159-4616
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