Supporting Information (SI)
A 1,8-Naphthyridine-based Fluorescent chemodosimeter for the Rapid Detection of Zn2+ and Cu2+ Ming-Ming Yu, Zhan-Xian Li, Liu-He Wei,* Dong-Hui Wei, MingSheng Tang*, Department of Chemistry, Zhengzhou University, Zhengzhou 450001, China
[email protected] Table of contents 1. Experimental
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2. Changes in Absorption and Emission Spectra of 1 upon Addition of Various Metal Ions
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3. Radiative Decay Curves of 1 in Methanol befoure, after Addition of Zn2+ and Cu2+
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4. X-ray Crystallography
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1. Experimental General instruments For chromatography, 160−200 mesh silica gel (Qingdao, China) was employed. 1H, 13C spectra were recorded on a Varian Mercury Bruker 400 spectrometer. Chemical shifts are reported in ppm using tetramethylsilane (TMS) as the internal standard. Mass spectra were obtained on a VG ZAB-HS mass spectrometer or a Finnigan LCQ mass spectrometer. All spectral measurements were carried out at 20˚C. UV-Vis absorption spectra were measured on a Hitachi UV-3100 spectrophotometer and fluorescence spectra were determined on a Hitachi F-4500 spectrophotometer. The fluorescence lifetime was obtained from an Edinburgh LhifeSpecps fluorescence lifetime spectrometer.
Synthetic procedure and characterization data Synthetic procedure of 1-(7-acetamino-1,8-naphthyridyl)-2-(6-diacetamino-pyridyl)-ethene (1): A mixture of 2-amino-3-aldehyde-pyridine (0.795g, 5mmol), 2-Amino-7-methyl-1,8-naphthyridine (0.61 g, 5 mmol), and acetic anhydride (20 mL) was stirred and refluxed at 140°C for 24h under N2. The mixture was subsequently poured into ice water (100 mL) and stirred overnight. The obtained yellow solid was filtered off, washed thoroughly with water, and dried to afford crude product. Pale yellow sample (1.5g) was obtained from column chromatography over silica gel column using chloroform/ethanol (10:1) as eluent. Yield: 80%. The structure of compound 1 was confirmed by m.p.,1H NMR, 13C NMR, FTIR, Elemental analysis, and X-ray crystal structure determination. Selected data for 1: mp 180 – 181 °C. 1H NMR (CDCl3, 400 MHz): δ (ppm) 8.59 (m, 1H), 8.53 (d, 1H, J= 8.8 Hz), 8.18 (m, 3H), 7.67 (d, 1H, J= 16.2 Hz), 7.56 (d, 1H, J= 8.3 Hz), 7.48 (m, 1H), 7.37 (d, 1H, J= 16.2 Hz), 2.33 (s, 9 H). 13C NMR (CDCl3, 100 MHz ): δ (ppm) 25.0, 26.7, 115.1, 120.0, 120.1, 124.9, 128.1, 131.2, 133.8, 136.1, 137.3, 139.4, 149.7, 150.8, 154.0, 157.9, 172.5. IR (KBr, cm-1): 3395, 1701, 1597, 1504, 1428, 1400, 1368, 1307, 1286, 1255, 1137, 1031, 850, 807. Elemental analysis calcd (%) for C21H19N5O3: C 64.77, H 4.92, N 17.98; found: C 64.35, H 5.22, N 17.61.
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H NMR of 1-(7-acetamino-1,8-naphthyridyl)-2-(6-diacetamino-pyridyl)-ethene (1):
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C NMR of 1-(7-acetamino-1,8-naphthyridyl)-2-(6-diacetamino-pyridyl)-ethene (1):
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Synthesis of 2-diacetamino-3-methyl-pyridine (4):
To the 2-amino-3-methyl-pyridine (2 g, 18.5 mmol) was added an excess of acetic anhydride, and the mixture was refluxed for 4 h. After cooling, it was filtered and pale yellow sample was obtained from column chromatography over silica gel column using dichloromethane as eluent. Yield: 70%. mp 67 – 68 °C. 1H NMR (CDCl3, 400 MHz): δ (ppm) 8.45 (m, 1H), 7.68 (m, 1H), 7.31 (m, 1H), 2.26 (s, 6H), 2.21 (s, 3H). 13C NMR (CDCl3, 100 MHz): δ (ppm) 17.2, 26.4, 124.5, 131.9, 140.1, 147.6, 151.7, 172.2. IR (KBr, cm-1): 3232, 3014, 1668, 1530, 1450, 1296, 1120, 809. Elemental analysis calcd (%) for C10H12N2O2: C 62.49, H 6.29, N 14.57; found: C 62.46, H 6.29, N 14.63.
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1
H NMR of 2-diacetamino-3-methyl-pyridine (4)
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C NMR of 2-diacetamino-3-methyl-pyridine (4)
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Synthesis of 7-acetamino-2-methyl-1,8-naphthyridine (5):
7-acetamino-2-methyl-1,8-naphthyridine was synthesized from 2,6-diaminopyridine according to reference method.1 Yield: 85%. mp 278 – 281 °C. 1H NMR (CDCl3): δ (ppm) 8.47 (d, 1H, J= 8.8 Hz), 8.14 (d, 1H, J= 2.4 Hz), 8.02 (d, 1H, J= 7.6 Hz), 7.28 (d, 1H, J= 11.6 Hz), 2.77 (s, 3H), 2.29 (s, 3H). 13C NMR (CDCl3): δ (ppm) 25.6, 77.0, 114.2, 121.6, 136.4, 139.1, 153.4, 163.3, 169.5. IR (KBr, cm-1): 3174, 3008, 1701, 1609, 1501, 1436, 1395, 1377, 1281, 1242, 1137, 1009, 853, 792, 623. Elemental analysis calcd (%) for C11H12N3O: C 65.66, H 5.51, N 20.88; found: C 65.88, H 5.60, N 20.79. References (1) (a) Kelly, T. R.; Zhao, C.; Bridger, G. J. J. Am. Chem. Soc. 1989, 111, 3744. (b) Kelly, T. R.; Bridger, G. J.; Zhao, C. J. Am. Chem. Soc. 1990, 112, 8024.
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1
H NMR of 7-acetamino-2-methyl-1,8-naphthyridine (5)
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C NMR of 7-acetamino-2-methyl-1,8-naphthyridine (5)
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2. Changes in Absorption and Emission Spectra of 1 upon Addition of Various Metal Ions
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B Fig. S1 Absorption spectra change of 1 (5.0 × 10−5 M) in methanol upon addition of Zn2+ (A) and Cu2+ (B). The metal ions is 2 equivalent to 1.
Fig. S2 Fluorescence emission spectra of 1 in ethanol upon addition of Zn2+ ion (λex = 362 nm).
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Fig. S3 Fluorescence emission spectra of 1 in ethanol upon addition of Cu2+ ion (λex = 362 nm).
Fig. S4 Fluorescence emission spectra of 1 in ethanol upon addition of Zn(NO3)2 (λex = 362 nm).
Fig. S5 Fluorescence emission spectra of 1 in ethanol upon addition of Cu(NO3)2 (λex = 362 nm).
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Fig. S6 Fluorescence emission spectra of 1 in ethanol upon addition of CuSO4 (λex = 362 nm).
Fig. S7 Fluorescence emission spectra of 1 in methanol upon addition of Ca2+ ion (λex = 362 nm).
Fig. S8 Fluorescence emission spectra of 1 in methanol upon addition of Cr3+ ion (λex = 362 nm).
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Fig. S9 Fluorescence emission spectra of 1 in methanol upon addition of Hg 2+ ion (λex = 362 nm).
Fig. S10 Fluorescence emission spectra of 1 in methanol upon addition of K+ ion (λex = 362 nm).
Fig. S11 Fluorescence emission spectra of 1 in methanol upon addition of Mg 2+ ion (λex = 362 nm).
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Fig. S12 Fluorescence emission spectra of 1 in methanol upon addition of Mn2+ ion (λex = 362 nm).
Fig. S13 Fluorescence emission spectra of 1 in methanol upon addition of Na+ ion (λex = 362 nm).
Fig. S14 Fluorescence emission spectra of 1 in methanol upon addition of Ni2+ ion (λex = 362 nm).
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3. Fluorescence Decay Curves of 1 in Methanol before, after Addition of Zn2+ and Cu2+.
Fig. S15 Fluorescence decay curve of 1 (2.5 × 10−5 M) in methanol.
Fig. S16 Fluorescence decay curve of 2 × 10−5 M solution of 1 in methanol after addition of 2 equiv Zn2+.
Fig. S17 Fluorescence decay curve of 2 × 10−5 M solution of 1 in methanol after addition of 2 equiv Cu2+.
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4. X-ray Crystallography Intensity data collection was carried out with a Bruker APEXII diffractometer equipped with a CCD detector using Mo Kα monochromatized radiation ( = 0.71073Å) at room temperature. The raw frame data were integrated into SHELXformat reflection files and corrected for Lorentz and polarization effects using SAINT [1]. Corrections for incident and diffracted beam absorption effects were applied using SADABS [1]. The structure was solved by direct method and refined by full-matrix least-squares method on F2 using the SHELXTL 97 software package [2]. All non-hydrogen atoms were refined anisotropically. Positions of hydrogen atoms attached to carbon atoms were fixed at their ideal positions, and those attached to oxygen atoms could not be located. Table 1. Crystallographic Data for 1 1 Empirical formula C26H26N4O4 Formula weight 452.48 Crystal size [mm] 0.26×0.24×0.22 T/K 292 crystal system Monoclinic space group P 2/c a/Å 7.975(1) b/Å 16.447(2) c/Å 19.293(3) α/deg 90 β/deg 99.295(9) γ/deg 90 V/Å3 2497.4(5) Z 4 ρcalcd/g cm-3 1.209 F(000) 968 Reflections collected 5843 Unique reflections 4413 Rint 0.0556 GOF(S) 1.531 data/restraints/paras 2570/0/188 Final R indices 0.0882 I > 2σ(I) 0.1607 R indices R1=0.1867 all data wR2=0.2051
X-ray crystal structures of 1, solvent molecules were deleted for clarity. [1] Bruker Analytical X-ray Systems, Inc.: Madison, WI, 1998. [2] G. M. Sheldrick, SHLEXL97, Program for Crystal Structure Refinement, University of Göttingen, Germany, 1997.
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Table 2. Crystallographic Data for 5-Zn Empirical formula Formula weight Crystal size [mm] T/K crystal system space group a/Å b/Å c/Å α/deg β/deg γ/deg V/Å3 Z ρcalcd/g cm-3 F(000) Reflections collected Unique reflections Rint GOF(S) data/restraints/paras Final R indices I > 2σ(I) R indices all data
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5-Zn C72H72Cl8N24Zn4 1818.68 0.22×0.20×0.16 294 Triclinic P -1 9.414(2) 13.961(3) 16.640(3) 90.71(2) 99.74(3) 109.21(3) 2030.0(8) 4 1.486 928 10772 7849 0.0246 1.079 10772/0/491 0.0542 0.1109 R1=0.0816 wR2=0.1323
