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Phosgene is a highly toxic substance that has become a serious potential threat to public health safety. A colorimetric and ratiometric fluorescence p...
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An ESIPT based fluorescence probe for colorimetric, ratiometric and selective detection of phosgene in solutions and the gas phase Liyan Chen, Di Wu, Jong-Man Kim, and Juyoung Yoon Anal. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.analchem.7b03988 • Publication Date (Web): 31 Oct 2017 Downloaded from http://pubs.acs.org on October 31, 2017

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An ESIPT based fluorescence probe for colorimetric, ratiometric and selective detection of phosgene in solutions and the gas phase Liyan Chen, †,§ Di Wu, †,§ Jong-Man Kim*,‡ and Juyoung Yoon*,† †

Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea Department of Chemical Engineering, Hanyang University, Seoul 04763, Korea *Correspondence : ‡

(J. Yoon) Email: [email protected], Fax: 82-2-3277-2385 (J.-M. Kim) Email: [email protected] ABSTRACT: Phosgene is a highly toxic substance that has become a serious potential threat to public health safety. A colorimetric and ratiometric fluorescence probe 1 for phosgene has been developed based on an ESIPT process. Both the visible colorimetric change to yellow from colorless and fluorescent color change from blue to green (under 365 nm hand-held UV lamp) can be easily observed by naked eye. Probe 1 has a high sensitivity and selectivity for phosgene in solutions and the gas phase. The mechanism for sensing by 1 was investigated by using high-resolution mass spectrometry, and 1H NMR and 13C NMR spectroscopies.

Phosgene (COCl2) is a colorless and severely poisonous gas.1-5 Exposure to phosgene gas causes great harm to the lungs of human beings and respiratory track, leading to asphyxia, pulmonary emphysema, pulmonary edema and sometimes even death.6-10 For this reason, phosgene has been utilized as a chemical warfare agent in World War I.11-15 However, in sharp contrast to nerve agents including Soman, Sarin and Tabun whose usages are controlled by international laws,16-17 phosgene has been widely used in industry particularly for the synthesis of pharmaceuticals and pesticides.18 As a highly toxic yet readily available chemical, phosgene has become a potential threat to public health. Thus, the detection of phosgene is of great importance and has attracted considerable attention. In contrast to conventional detection systems, such as those employing gas chromatographic19-22 and electrochemical methods,23-26 fluorescence probes utilizing small molecules have been investigated extensively and widely used due to their high sensitivity and selectivity, simple operations and capabalities of real-time detection.27-38 However, in contrast to those developed for detection of nerve agent mimics,39-51 fluorescence probes for phosgene are limited52-61 and limitations exist in the use of some of those that have been developed thus far. For example, the selectivity of some of the reported probes for phosgene and nerve gas mimics has not yet been evaluated.52-55 In addition, some of the previously developed phosgene fluorescence probes rely on the use of reaction groups that can be interfered with by formaldehyde and nitric oxide,62-64 while others cannot discriminate between triphosgene and phosgene because they contain tertiary amine groups which catalyze the decomposition of triphosgene to phosgene.65 Moreover, only two of the these probes display ratiometric fluorescence responses to phosgene.59,60

Because the effective internal referencing can greatly increase the sensitivity of probes and improve quantification of the target, ratiometric66 fluorescence probes for phosgene are in great demand. To design probes of this type, the following basic requirements need to be met. Firstly, the probe should contain dual sites for reaction with phosgene such as an amine (imine), hydroxyl or carboxylic acid. Secondly, the probe should not contain a tertiary amine group, which catalyzes the decomposition of triphosgene to phosgene. Finally, a large difference should exist between the emission wavelength maxima of the probe and the product formed through the reactions between the probe and phosgene. With these requirements in mind, we envisaged that the fluorophore based on excited state intramolecular proton transfer (ESIPT) would serve as a suitable ratiometric fluorescence probe 1 for phosgene. As shown in scheme 1, upon photoexcitated, 1 should promote ESIPT and consequent formation of keto tautomer, which possesses dual sites for a two-fold carbamylation reaction with phosgene to yield the tetracyclic product 2. The wavelength of fluorescence from 2 should be different from that of 1 owing to the strong electronwithdrawing property of carbonyl group in the former substance. Moreover, ESIPT fluorophores in general should have a large Stokes shift, which will be beneficial to fluorescence analysis as consequence of their abilities to avoid the self-absorption and inner filtering effects.67-75 In order to investigate the design proposed above (Scheme 1), probe 1 was successfully synthesized through an simple step starting from the commercially available aminothiophenol and benzoic acid in the presence of tetrabutylammonium bromide (TBAB) and triphenyl phosphate.76

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EXPERIMENTAL SECTION Reagents and Materials. Unless otherwise mentioned, all the materials were purchased from the commercially available suppliers and were used directly without the further purifications. UV absorption spectroscopy detection was operated on Scinco S-3100 using a 1 cm optical path length cell at room temperature. Fluorescence emission spectrum was obtained using the RF-5301/PC spectrofluorophotometer. All flash column chromatographies were performed using 200-300 mesh silica gel. 1H NMR and 13C NMR spectra were recorded on a Bruker 300 MHz instrument. The high resolution mass spectra (HRMS) were measured on a Jeol JMS 700 high resolution mass spectrometer. Synthesis of Probe 1.76 Triphenyl phosphite (TPP) (1.0 mmol, 326 mg), tetrabutylammonium bromide (TBAB) (1.2 mmol, 398 mg), 2-aminothiophenol (1.0 mmol, 125 mg) and benzoic acid (1.0 mmol, 151 mg) were well mixed in the 25 mL round bottomed flask. This mixture was then placed in an oil bath and heated to 120 oC. The solution was stirred overnight at this temperature. Then 30 mL MeOH was added to the mixture and the product was precipitated from the viscous solution. The resulting solid was filtered off and purified by column to give the final product probe 1 with 73% yield (175 mg). The structure of 1 was assigned by using 1H NMR and 13C NMR spectroscopies, and high-resolution mass spectrometry. The Determination of the Fluorescence Quantum Yield. The fluorescence quantum yields of 1 and 2 were determined in CHCl3 with quinine sulfate (Φ = 0.58, in 1 N H2SO4) as the reference. The quantum yields were calculated using the following equation: Φx=Φs[(AsFx/AxFs)(nx2/ns2)]. Where, Ax and As are the absorbance of quinine sulfate and sample solutions at the same excitation wavelength; Fx and Fs are the corresponding integrated fluorescence intensities of quinine sulfate and sample solutions; ns and nx are the refractive index of 1N H2SO4 and chloroform. Preparation of Filter Papers with Probe 1. 1 mg probe 1 and 1 g polyethylene oxide were dissolved in dichloromethane (50 mL). A filter paper was cut to 1 cm*4 cm and immersed in the solution. The filter papers were taken out from the solution and dry in air. Detection of phosgene gas with filter papers. The resultant paper stripes were placed in the flask (250 mL). To the flask was separately added phenanthridine and triphosgene. The flask was sealed and then heated to 120 oC. The concentrations of gas phosgene were estimated as following: 0.8 mg/L (0.2 mg phenanthridine and 0.2 mg triphosgene); 2.4 mg/L (0.6 mg phenanthridine and 0.6 mg triphosgene); 4 mg/L (1.0 mg phenanthridine and 1.0 mg triphosgene) according to the

A) 0.40 1 eq. Triphosgene 0.32

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Scheme 1. Synthetic procedures of 1 and proposed detection mechanism with phosgene.

reference;53 After 10 mins, the flask was cooled down and treated with ethanol. RESULTS AND DISCUSSION Fluorescence Response to Phosgene. The capability of 1 to serve as a probe for phosgene in chloroform solution was assessed. In this study, phosgene is generated by addition of triphosgene to solutions containing triethylamine (TEA). As can be seen by inspecting the image in Figure 1, a solution of 1 in chloroform (10 µM) is colorless (λmax = 375 nm) and it displays blue emission with a maximum at 445 nm (Φ = 0.12). Upon addition of triphosgene in the presence of TEA, the absorption maximum of 1 changes to 450 nm with an associated color change to yellow (Figure 1A inset). Accompanied with the color change, the intensity of fluorescence at 445 nm decreases concurrently with an increase in the intensity at 495 nm (Φ = 0.34) in association with a gradually emission color change to green (Figure 1B inset). Moreover, the good linearity exists in a plot of the ratio of emission intensity at 495 and 445 nm and triphosgene concentration in the 0–3.0 µM range (Figure S1). The detection limit of 1 for phosgene sensing was determined as 0.14 ppm (based on 3δ/k), a value far below that (2 ppm) which causes immediate danger to health and life (IDLH).24, 54

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Figure 1. A) UV-vis spectra of 1 (10 µM) was obtained upon additions of triphosgene (0-10 µM) in the presence of TEA (10 µM) in chloroform; B) Fluorescence spectra of 1 (10 µM) was obtained upon additions of triphosgene (0-10 µM) in the presence of TEA (10 µM) in chloroform; All the spectra were obtained after incubation with different concentrations of triphosgene for 10 min; λex = 375 nm, λem1 = 445 nm, λem2= 495 nm, Slits: 3/5 nm; Figure 1A) Inset: Photographic images showing the color change

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of a solution of probe 1 (10 µM) after addition of triphosgene (6 µM) in the presence of triethylamine (10 µM); Figure 1B) inset: Photographic images of fluorescence change of solutions of probe 1 (10 µM) after the additions of different concentrations of triphosgene ((1) 0 µM; (2) 2 µM; (3) 4 µM; (4) 6 µM) in the presence of triethylamine (10 µM) under 365 nm hand-held UV lamp.

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Kinetic Study. The rate constant for reaction of 1 with phosgene was detected through the time-dependence model of fluorescent responses (Figure 2 and Figure S2). Upon addition of triphosgene (6 µM) to a CHCl3 solution of 1 (10 µM) containing TEA (10 µM), the fluorescence intensity at 495 nm increases with time and reaches a plateau after 5 mins (Figure S2). Based on the kinetic data for reactions of 1 with phosgene, the pseudo-first-order rate constant (kobs) was determined as 2.5 × 10−1 min−1. In the absence of TEA, reaction of 1 with triphosgene (6 µM) occurs much more slowly as is reflected by the observation that the fluorescence intensity increases only 2 folds after 5 mins. However, addition of TEA (10 µM) to this solution causes the fluorescence intensity to increase reaching a maximum within 4 mins (Figure 2)

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Figure 2. Time-dependence detections in the fluorescent intensity at 495 nm for solutions of probe 1 (10 µM) following addition of triphosgene (6 µM) for 5 mins, and then addition of TEA (10 µM); λex = 375 nm, slit: 3/5 nm.

Selectivity Study for Sensing Phosgene. The fluorescence response of 1 to related analytes was investigated next to determine if this probe can be employed to detect phosgene selectively. As is seen by viewing Figure 3, only phosgene triggers an obvious ratiometric change in the fluorescence of CHCl3 solutions of 1 (Figure 3A). Specifically, solutions of 1 do not display changes in their fluorescence profiles when other analytes like SOCl2, CH3COCl, TosCl, DCP, SO2Cl2 and POCl3 are added. The ratios of fluorescence intensities at 495 and 445 nm (F495/F445) as a function of the analytes added are shown in Figure 3B. The data indicate that a high selectivity exits for 1 towards phosgene. In addition, inspection of solutions containing 1 under a 365 nm hand-held UV lamp and following the addition of various analytes (Figure 3B, insert) also show that phosgene alone leads to an obvious fluorescence color change from blue to green. The fluorescence responses of 1 to formaldehyde and nitric oxide have also been investigated because some previously reported phosgene probes are interfered with by these species (Figure S3 and Figure S4).62-64 The results show that neither of these substances promotes an observable change in the absorption or emission profiles of 1.

Figure 3. A) Fluorescence response and B) ratios of fluorescence intensity changes (F495/F445)of a solution of probe 1 (10 µM) in chloroform before and after addition of phosgene (6 µM), triphosgene (10 µM) or various analytes (100 µM) : (1) blank, (2) SOCl2, (3) CH3COCl, (4) TosCl, (5) DCP, (6) SO2Cl2, (7) POCl3, (8) Triphosgene (10 µM ), (9) Phosgene (Triphosgene (6 µM)/ Et3N (10 µM)); λex = 375 nm, slits: 3/5 nm; Inset: Photographs of solutions of probe 1 in chloroform under 365 nm UV hand-held lamp after addition of different analytes.

Sensing Mechanism. To confirm the proposed detection mechanism of operation of probe 1 (Scheme 1), the product 2, which is obtained by reaction of probe 1 with triphosgene in the presence of TEA, was isolated in 91 % yield and subjected to 1H NMR and 13C NMR spectroscopic analysis (see ESI). Parts of the 1H NMR spectra of 1 and 2 are displayed in the Figure 4. Reaction with phosgene causes the NH2 proton resonance at 7.15 ppm in 1 to disappear. Moreover, the aromatic proton signals in the spectrum of 1 are shifted downfield in the spectrum of 2. To gain further evidence for the operation of the proposed sensing mechanism, a solution of 1 and triphosgene (1 equivalent) in presence of TEA (1 equivalent) was analyzed by using HRMS. The new peak at 267.0597 (M+H+) that is observed to arise following the reaction of probe 1 and phosgene is in good accordance with that calculated (267.0587 (M+H+)) for 2 (Figure S5). Detection in the Gas Phase. In the terminal phase of the study, we demonstrated that 1 can be utilized for detecting phosgene gas. For this purpose, polyethylene oxide was used to immobilize 1 on filter papers (see ESI). The paper containing 1 displays blue emission under a 365 nm hand-held UV lamp. However, the color of the fluorescence changes to green after

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Figure 4. Partial 1H NMR spectra of 1 (top) and product 2 (DMSO-d6, 300 MHz).

the paper is exposed to gaseous phosgene (concentration estimated as 0-4.0 mg/L), which is generated by the reaction of triphosgene with phenanthridine (Figure 5).53 In concert with the fluorescence change, the colors of the papers change from colorless to yellow, an event readily observed using the naked eye (Figure S6). Furthermore, the selectivity of the test paper to phosgene gas over other related analytes was also evaluated (Figure 6). While a slight fluorescence color change occurs when the paper is exposed to triphosgene, which is likely caused by phosgene, none of the other analysts promotes the same ratiometric fluorescence or color change that phosgene gas does (Figure S7). The combined results verify that 1 has the potential capabilities of being used to selectively and sensitively detect phosgene in both the solution and the gas phase.

generated by 1.0 mg triphosgene and 1.0 mg phenanthridine).

CONCLUSION In summary, by taking advantage of the fact that 2-(2aminophenyl)benzothiazole (ABT) undergoes an ESIPT process to generate dual sites for reaction with phosgene, we have developed the new colorimetric and ratiometric fluorescence probe 1 for detection of phosgene. The probe can be employed to detect this toxic agent in solutions and the gas phase, and in a colorimetric and ratiometric manner. Both the visible colorimetric change from colorless to yellow and fluorescent color change from blue to green (by aid of the hand-held UV lamp (365 nm)) can be observed by using the naked eye. Moreover, the probe displays high sensitivity with the detection limit as low as 0.14 ppm and selectivity towards phosgene over other relevant analytes including triphosgene. The results show that 1 is a promising addition to the very limited family of ratiometric fluorescence probes for phosgene. Investigations of differently substituted ABT derivatives for detecting phosgene are ongoing in our laboratory.

ASSOCIATED CONTENT Figure 5. Photographs of the fluorescence of test papers containing absorbed probe 1 exposed for 10 mins to vapors containing various amounts of triphosgene and phenanthridine in 250 mL flask. (1) 0 mg/L, (2) 0.2 mg triphosgene and 0.2 mg phenanthridine (0.8 mg/L phosgene gas); (3) 0.6 mg triphosgene and 0.6 mg phenanthridine (2.4 mg/L phosgene gas) and (4) 1.0 mg triphosgene and 1.0 mg phenanthridine (4 mg / L phosgene gas).

Supporting Information The Supporting Information is available free of charge on the ACS Publications website. Extraction of mechanism study, the synthetic pathway, NMR and Mass spectrum of the probe

AUTHOR INFORMATION Corresponding Author *Juyoung Yoon: [email protected]; Fax: 82-2-3277-2385. *Jong-Man Kim: [email protected];

Author Contributions §

Figure 6. Photographic images showing the fluorescence of test papers containing absorbed probe 1 exposed for 10 mins to phosgene and the vapors of various analytes. The analytes tested were (1) blank, (2) SOCl2, (3) CH3COCl, (4) TosCl, (5) DCP, (6) SO2Cl2, (7) POCl3, (8) Triphosgene, (9) Phosgene (4 mg / L

These authors contributed equally to this work.

Notes The authors declare no competing financial interest.

ACKNOWLEDGMENT

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This study is financially supported by the grants from the National Creative Research Initiative programs of the National Research Foundation of Korea (NRF) funded by the Korean government (MSIP) (No. 2017R1A2A1A05000752 and 2012R1A3A2048814). Jeol JMS 700 high resolution mass spectrometer was used for all the mass spectral data which was supported from the Korea Basic Science Institute (Daegu).

REFERENCES (1) Babad, H.; Zeiler, A. G. Chem. Rev. 1973, 73, 75-91. (2) Noort, D.; Hulst, A. G.; Fidder, A.; van Gurp, R. A.; de Jong, L. P. A.; Benschop, H. P. Chem. Res. Toxicol. 2000, 13, 719-726. (3) Borak, J.; Diller, W. F.; Habil, M. J. Occup. Environ. Med. 2001, 43, 110-119. (4) Li, W.; Liu, F.; Wang, C.; Truebel, H.; Pauluhn, J. Toxicol. Sci. 2013, 131, 612-628. (5) Kodavanti, U. P.; Costa, D. L.; Giri, S. N.; Starcher, B.; Hatch, G. E. Fundam. Appl. Toxicol. 1997, 37, 54-63. (6) Sciuto, A. M. Arch. Toxicol. 1998, 72, 283-288. (7) Holmes, W. W.; Keyser, B. M.; Paradiso, D. C.; Ray, R.; Andres, D. K.; Benton, B. J.; Rothwell, C. C.; HoardFruchey, H. M.; Dillman, J. F.; Sciuto, A. M.; Anderson, D. R. Toxicol. Lett. 2016, 244, 8-20. (8) Cucinell, S. A.; Arsenal, E. Arch. Environ. Health. 1974, 28, 272-275. (9) Staub, N. C. Physiol. Rev. 1974, 54, 678-811. (10) Sciuto, A. M.; Stotts, R. R.; Hurt, H. H. J. Appl. Toxicol. 1996, 16, 381-384. (11) Evison, D.; Hinsley, D.; Rice, P. Br. Med. J. 2002, 324, 332-335. (12) Karalliedde, L.; Wheeler, H.; Maclehose, R.; Murray, V. Public. Health., 2000, 114, 238-248. (13) S. L. Bartelt-Hunt, V.; Knappe, D. R. U.; Barlaz, M. A. Crit. Rev. Environ. Sci. Technol. 2008, 38, 112-136. (14) Yang, Y.-C.; Baker, J. A.; Ward, J. R. Chem. Rev. 1992, 92, 1729-1743. (15) Hill, H. H.; Martin, S. J. Pure. Appl. Chem. 2002, 74, 2281-2291. (16) Price, R. International Organization, 1995, 49, 73-103. (17) Sidell, F. R.; Borak, J. Ann. Emerg. Med. 1992, 21, 865871. (18) Collins, J. J.; Molenaar, D. M.; Bowler, L. O.; Harbourt, T. J.; Carson, M.; Avashia, B.; Calhoun, T.; Vitrano, C.; Ameis, P.; Chalfant, R.; Howard, P. J. Occup. Environ. Med. 2011, 53, 239-244. (19) Davydova, M.; Kromka, A.; Exnar, P.; Stuchlik, M.; Hruska, K.; Vanecek, M.; Kalbac, M. Pure Appl. Chem., 2002, 74, 2281-2291 (20) Priestley, L. J.; Cretchfield, F. E.; Ketcham, N. H.; Cavender, J. D. Anal. Chem. 1965, 37, 70-71 (21) Jeltes, R.; Burghardt, E.; Breman, J. Br. J. Ind. Med. 1971, 28, 96-99; d) Esposito, G. G.; Lillian, D.; Podolak, G. E.; Tuggle, R. M. Anal. Chem. 1977, 49, 1774-1778. (22) Palit, M.; Pardasani, D.; Gupta, A. K.; Dubey, D. K. Anal. Chem. 2005, 77, 711-717. (23) Davydova, M.; Kromka, A.; Exnar, P.; Stuchlik, M.; Hruska, K.; Vanecek, M.; Kalbac, M. Phys. Status Solidi A. 2009, 206, 2070-2073. (24) Virji, S.; Kojima, R.; Fowler, J. D.; Villanueva, J. G.; Kaner, R. B.; Weiller, B. H. Nano. Res. 2009, 2, 135-142. (25) Toon, G. C.; Blavier, J. -F.; Sen, B.; Drouin, B. J. Geophys. Res. Lett. 2001, 28, 2835-2838. (26) Singh, H. B.; Lillian, D.; Appleby, A. Anal. Chem. 1975, 47, 860-864.

(27) Gao, M.; Yu, F.; Lv, C.; Choo, J.; Chen, L. Chem. Soc. Rev. 2017, 46, 2237-2271. (28) Hou, J. T.; Ren, W. X.; K. Li, Seo, J.; Sharma, A.; Yu, X. Q.; Kim, J. S. Chem. Soc. Rev., 2017, 46, 2076-2090. (29) He, L.; Dong, B.; Liu, Y.; Lin, W. Chem. Soc. Rev. 2016, 45, 6449-6461. (30) Sun, W.; Guo, S.; Hu, C.; Fan, J.; Peng, X. Chem. Rev., 2016, 116, 7768-7817. (31) Vendrell, M.; Zhai, D.; Er, J. C.; Chang, Y. T. Chem. Rev., 2012, 112, 4391-4420 (32) Wu, D.; Chen, L.; Kwon, N.; Yoon, J. Chem, 2016, 1, 674-698. (33) Li, X.; Gao, X.; Shi, W.; Ma, H. Chem. Rev. 2014, 114, 590-659 (34) Yang, Y.; Zhao, Q.; Feng, W.; Li, F. Chem. Rev. 2013, 113, 192-270. (35) Chen, X.; Wang, F.; Hyun, J. Y.; Wei, T.; Qiang, J.; Ren, X.; Shin, I.; Yoon, J. Chem. Soc. Rev. 2016, 45, 2976-3016. (36) Liu, Y.; Hu, Y.; Lee, S.; Lee, D.; Yoon, J. Bull. Korean Chem. Soc. 2016, 37, 1661-1678. (37) Thambi, T.; Park, J. H.; Lee, D. S. Chem. Commun. 2016, 52, 8492-8500. (38) Xu, W.; Zeng, Z.; Jiang, J.-H.; Chang, Y.-T.; Yuan, L. Angew. Chem. Int. Ed., 2016, 55, 13658-13699. (39) Kim, K.; Tsay, O. G.; Atwood D. A.; Churchill, D. G. Chem. Rev., 2011, 111, 5345-5403. (40) Jang, Y. J.; Kim, K.; Tsay, O. G.; Atwood, D. A.; Churchill, D. G. Chem. Rev. 2015, 115, PR1-PR76. (41) Yue, G.; Su, S.; Li, N.; Shuai, M.; Lai, X.; Astruc, D.; Zhao, P. Coordin. Chem. Rev. 2016, 311, 75-84. (42) Cai, Y.-C.; Li, C.; Song, Q.-H. ACS Sens. 2017, 2, 834– 841. (43) Mahapatra, A. K.; Maiti, K.; Manna, S. K.; Maji, R.; Mondal, S.; Mukhopadhyay, C. D.; Sahoo, P.; Mandal, D. Chem. Commun., 2015, 51, 9729-9732. (44) Hu, X.-X.; Su, Y.-T.; Ma, Y.-W.; Zhan, X.-Q.; Zheng, H.; Jiang, Y. B. Chem. Commun. 2015, 51, 15118-15121 (45) Kumar, V.; Rana, H.; Chem. Commun. 2015, 51, 1649016493. (46) Jang, Y. J.; Mulay, S. V.; Kim, Y.; Jorayev, P.; Churchill, D. G. New J. Chem. 2017, 41, 1653-1658. (47) Huang, S.; Wu, Y.; Zeng, F.; Sun, L.; Wu, S. J. Mater. Chem. C. 2016, 4, 10105-10110. (48) Climent, E.; Biyikal, M.; Gawlitza, K.; Dropa, T.; Urban, M.; Costero, A. M.; Martinez-Manez, R.; Rurack, K. Chem. Eur. J. 2016, 22, 11138-11142 (49) Sun, X.; Dahlhauser, S. D.; Anslyn, E. V. J. Am. Chem. Soc. 2017, 139, 4635-4638. (50) Kim, Y.; Jang, Y. J.; Mulay, S. V.; Nguyen, T.-T.; Churchill, D. G. Chem. Eur. J., 2017, 23, 7785-7790. (51) Sun, X.; Reuther, J. F.; Phillips, S. T.; Anslyn, E. V. Chem. Eur. J., 2017, 23, 3903-3909. (52) Zhang, H.; Rudkevich, D. M. Chem. Commun. 2007, 1238-1239. (53) Wu, X.; Wu, Z.; Yang, Y.; Han, S. Chem. Commun. 2012, 48, 1895-1897. (54) Kundu, P.; Hwang, K. C. Anal. Chem. 2012, 84, 45944597. (55) Hu, Y.; Chen, L.; Jung, H.; Zeng, Y.; Lee, S.; Swamy, K. M.; Zhou, X.; Kim, M. H.; Yoon, J. ACS Appl. Mater. Interfaces 2016, 8, 22246-22252. (56) Zhou, X.; Zeng, Y.; Liyan, C.; Wu, X.; Yoon, J. Angew. Chem. Int. Ed. 2016, 55, 4729-4733. (57) Xia, H.-C.; Xu, X.-H.; Song, Q.-H. ACS Sens, 2017, 2, 178-182. (58) Xia, H.-C.; Xu, X.-H.; Song, Q.-H. Anal. Chem. 2017, 89, 4192-4197.

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(59) Zhang, Y.; Peng, A.; Jie, X.; Lv, Y.; Wang, X.; Tian, Z. ACS Appl. Mater. Interfaces, 2017, 9, 13920-13927. (60) Wang, S.-L.; Zhong, L.; Song, Q.-H. Chem. Commun. 2017, 53, 1530-1533. (61) Zhang, W.-Q.; Cheng, K.; Yang, X.; Li, Q.-Y.; Zhang, H.; Ma, Z.; Lu, H.; Wu, H.; Wang, X.-J. Org. Chem. Front., 2017, 4, 1719-1725. (62) He, L.; Yang, X.; Ren, M.; Kong, X.; Liu, Y.; Lin, W. Chem. Commun. 2016, 52, 9582-9585. (63) Li, Z.; Xue, Z.; Wu, Z.; Han, J.; Han, S. Org. Biomol. Chem., 2011, 9, 7652-7654. (64) Sun, Y. Q.; Liu, J.; Zhang, H.; Huo, Y.; Lv, X.; Shi, Y.; Guo, W. J. Am. Chem. Soc. 2014, 136, 12520-12523. (65) Pasquato, L.; Modena, G.; Cotarca, L.; Delogu, P.; Mantovani, S. J. Org. Chem., 2000, 65, 8224-8228. (66) Lee, M. H.; Kim, J. S.; Sessler, J. L. Chem. Soc. Rev. 2015, 44, 4185-4191. (67) Zhao, J.; Ji, S.; Chen, Y.; Guo, H.; Yang, P. Phys. Chem. Chem. Phys. 2012, 14, 8803-8817. (68) Chen, L.; Wu, D.; Lim, C. S.; Kim, D.; Nam, S. J.; Lee, W.; Kim, G.; Kim, H. M.; Yoon, J. Chem. Commun. 2017, 53, 4791-4794. (69) Sedgwick, A. C.; Sun, X.; Kim, G.; Yoon, J.; Bull, S. D.; James, T. D. Chem. Commun. 2016, 52, 12350-12352. (70) Huang, Z.; Ding, S.; Yu, D.; Huang, F.; Feng, G. Chem. Commun. 2014, 50, 9185-9187. (71) Ding, S.; Feng, G. Sensor. Actuat. B- Chem. 2016, 235, 691-697. (72) Luo, W.; Liu, W. J. Mater. Chem. B, 2016, 4, 3911-3915. (73) Yang, X.; Guo, Y.; Strongin, R. M. Angew. Chem. Int. Ed. 2011, 50, 10690 –10693. (74) Li, X.; Tao, R.-R.; Hong, L.-J.; Cheng, J.; Jiang, Q.; Lu,Y.-M.; Liao, M.-H.; Ye, W.-F.; Lu, N.-N.; Han, F,; Hu, Y.-Z. and Hu, Y.-H. J. Am. Chem. Soc. 2015, 137, 12296−12303. (75) Zhang, J.; Guo, W. Chem. Commun. 2014, 50, 4214-4217. (76) Meghdadi, S.; Amirnasr, M.; Ford, P. C. Tetrahedron Lett., 2012, 53, 6950-6953.

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