Electronic Supplementary Information (ESI) A TPE-oxazoline molecular switch with tunable multi-emission in both solution and solid state Qingkai Qi a, Xiaofeng Fang b, Yifei Liu* b, Peng Zhou b, Yumo Zhang a, Bing Yang a, Wenjing Tian a and Sean Xiao-An Zhang* a a State Key Lab of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China. Fax: +86-0431-85153812; E-mail: seanzhang@jlu.edu.cn b College of Chemistry, Jilin University, Changchun 130012, China. Fax: +86-0431-85153812; E-mail: liuyifei@jlu.edu.cn General information for synthesis and characterizations Materials Tetrahydrofuran (THF), toluene and ethanol were distilled in the presence of sodium benzophenoneketyl, calcium hydride and magnesium respectively, then, stored under nitrogen immediately prior to use. Dimethylformamide (DMF) was distilled and dried over potassium hydroxide. 4-bromobenzophenone was purchased from Alfa Aesar. Diphenylmethane, n-butyllithium (n-buli), p-toluenesulfonic acid (PTSA), 2-bromoethanol and all the other chemicals were purchased from Aladdin and used as received without further purification. Instruments 1 H NMR spectra were recorded on a 500 MHz BrukerAvance in CDCl 3 solutions, using CDCl 3 as solvent and tetramethylsilane (TMS) as an internal standard (δ = 0.00 ppm). 13 C NMR spectra were recorded on a 500 MHz BrukerAvance or a Varian-300 EX spectrometer spectrometer, using CDCl 3 as a solvent and CDCl 3 as an internal standard (δ = 77.00 ppm). LC-HRMS was obtained by Agilent 1290- microtof Q II. UV-Vis spectra were measured on a Shimadzu UV-2550 spectrophotometer. Fluorescence spectra of all samples were measured with a RF-5301PC spectrofluorometer. Single crystal X-ray diffraction intensity data were collected at was performed on an R-AXIS RAPID-F X-Ray Single Crystal Diffractometer. Powder XRD patterns were obtained from a PANalytical B.V.Empyrean X-ray diffractomer with Cu-Kα radiation (λ = 1.5418 Ǻ) at 25 o C (scan range: 4-50 o ).
Synthesis and characterizations Tetraphenylethene-oxazoline (TPE-OX) was prepared according to the synthetic routes shown in Scheme S1. Compound 1, 2 was synthesized according to the literature method. 1-3 N-(2-hydroxyethyl)-2,3,3-trimethylindoleine Bromide (3) was synthesized according to previous literatures. 4, 5 Scheme S1. Synthetic route to pre-tpe-ox and TPE-OX. Synthesis of pre-tpe-ox: A solution of 2 (0.79 g, 2.2 mmol) and 3 (0.56 mg, 2 mmol) in dry EtOH (15 ml) was refluxed under nitrogen for 16 h. After cooled to ambient temperature, the solvent was evaporated under reduced pressure. Then it was washed with diethyl ether (3 20 ml) and filtered, and the solid was re-crystallized with CH 2 Cl 2 and n-hexane to get red crystals (0.56 g, 45%). Synthesis of TPE-OX: A solution of 2 (0.72 g, 2 mmol) and 3 (0.62 mg, 2.2mmol) in dry EtOH (15 ml) was refluxed under nitrogen for 16 h. After cool to ambient temperature, the solvent was evaporated under reduced pressure. The residues was washed by Na 2 CO 3 aqueous solution and extracted by dichloromethane (DCM). The organic phase was dried and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel, ethyl acetate/petroleum ether =1/40, v/v) to give a pale yellow solid (0.44g, 40%). 1-(4-bromophenyl)-1,2,2-triphenylethene (1). 1 H NMR (500 MHz, CDCl 3 ), δ (TMS, ppm): 7.22 (d, J = 8.5 Hz, 2H), 7.15 7.08 (m, 9H), 7.05 6.99 (m, 6H), 6.90 (d, J = 8.5 Hz, 2H).
4-(1,2,2-Triphenylvinyl)benzaldehyde (2). 1 H NMR (500 MHz, CDCl 3 ), δ (TMS, ppm): 9.90 (s, 1H), 7.61 (d, J = 8.2 Hz, 2H), 7.19 (d, J = 8.2 Hz, 2H), 7.13 7.10 (m, 9H), 7.05 6.99 (m, 6H). LC-HRMS (ESI): m/z 361.1582 [(M+H) +, calcd: m/z :361.1587]. Pre-TPE-OX 1 H NMR (500 MHz, CDCl 3 ) δ (ppm): 8.19 (d, J = 16.0 Hz, 1H), 8.10 8.00 (m, 3H), 7.66 (d, J = 6.5 Hz, 1H), 7.60 7.51 (m, 3H), 7.23 (d, J = 7.7 Hz, 2H), 7.17 6.95 (m, 17H), 5.00 (s, 2H), 4.20 (s, 2H), 1.83 (s, 6H). 13 C NMR (125 MHz, CDCl 3 ) δ (ppm): 183.23, 154.73, 150.73, 143.31, 143.17, 143.07, 143.00, 142.73, 140.62, 140.03, 132.53, 131.89, 131.38, 131.28, 131.23, 131.16, 129.66, 129.63, 127.93, 127.89, 127.63, 127.08, 126.86, 126.83, 122.49, 115.07, 113.47, 59.36, 52.31, 50.68, 27.43. LC-HRMS (ESI): m/z 546.2794 [(M-Br) +, calcd: m/z : 546.2791]. TPE-OX 1 H NMR (500 MHz, CDCl 3 ) δ (ppm): 7.20 6.98 (m, 22H), 6.95 6.91 (m, 1H), 6.80 6.74 (m, 2H), 6.20 (d, J = 15.9 Hz, 1H), 3.79 3.40 (m, 4H), 1.42 (s, 3H), 1.14 (s, 3H). 13 C NMR (75 MHz, CDCl 3 ) δ (ppm): 150.54, 143.66, 143.39, 141.09, 140.44, 139.74, 134.421, 131.97, 131.61, 131.33, 131.28, 127.78, 127.66, 127.59, 127.52, 126.49, 126.45, 126.40, 126.06, 125.60, 122.33, 121.62, 111.95, 109.86, 63.48, 50.04, 47.94, 28.40, 20.31. LC-HRMS (ESI): m/z 546.2794 [(M+H) +, calcd: m/z : 546.2791]. Sample preparation for AIE measurement AIE performance of TPE-OX: Stock THF solution of TPE-OX with a concentration of 1 10-3 M was prepared. Transfer 1 ml of the stock solution to 10 ml volumetric flasks. After appropriate amount of THF were added, water was added dropwise under vigorous stirring to prepare 1 10-4 M solutions with different water fractions (0 90 vol %). The PL spectra measurements of the resulting solutions were then performed immediately. AIE and ring-closing synergistic behavior of pre-tpe-ox: Stock THF solution of CF TPE-OX with a concentration of 1 10-2 M was prepared. Transfer 100 ul of the stock solution to 10 ml volumetric flasks. Then 30 equiv of HCl solution (V<30 ul) were added into the volumetric flasks. After appropriate amounts of THF were added, water was added dropwise under vigorous stirring to prepare 1 10-4 M solutions with different water contents (0 99 vol %). The PL measurements of the resulting solutions were then performed immediately.
Table S1. Summary of crystal data and intensity collection parameters of pre-tpe-ox and TPE-OX. pre-tpe-ox TPE-OX Empirical formula C 41 H 38 BrCl 2 NO C 40 H 35 NO Formula weight 711.53 545.69 Crystal dimensions, mm 0.26 x 0.23 x 0.21 0.41 x 0.24 x 0.12 Crystal system Orthorhombic Triclinic Space group P2(1)2(1)2(1) P-1 a, Å 10.788(2) 11.086(7) b, Å 12.438(3) 12.646(9) c, Å 27.874(6) 12.710(7) α, deg 90 75.39(2) β, deg 90 68.94(2) γ, deg 90 67.74(2) V, Å 3 3740.2(14) 1524.9(17) Z 4 2 D calcd., g/cm 3 1.264 1.188 F 000 1472 580 Temp, (K) 291(2) 291(2) Μ(Mo Kα), mm -1 1.273 0.070 θ range, deg 3.28-25.00 3.07-25.00 No. of collected reflns. 27891 12022 No. of unique reflns. 6574 5313 R(int) 0.0962 0.063 Data/restraints/parameters 6574/0/418 5313/7/ 381 R 1, wr 2 [obs I> 2σ (I)] 0.0535, 0.1032 0.0755, 0.2012 R 1, wr 2 (all data) 0.1208, 0.1229 0.1651, 0.2659 Residual peak/hole e. Å -3 0.350/-0.330 0.405/-0.299 Goodness-of-fit on F 2 0.945 0.962 CCDC number 921512 921513
Fig. S1 UV-vis spectra of TPE-OX in THF (1 10-4 M) after addition of different equiv of HCl aqueous solution (volume less than 0.3% of total volume). Fig. S2 PL spectra and fluorescent images of TPE-OX and pre-tpe-ox crystals.
Fig. S3 Dihedral angles of benzene ring in indole and the directly connected benzene ring of TPE in single crystals of TPE-OX (A) and pre-tpe-ox (B). Fig. S4 Molecular orbital amplitude plots of HOMO and LUMO energy levels of TPE-OX and pre-tpe-ox crystals calculated using B3LYP/6-31G(d) by Gaussian 09.
Figure S5. Uv-vis spectra (A) and PL spectra (B) of TPE-OX in POF in THF cyclohexane (v/v) mixtures with different fraction of cyclohexane (f ch ). Fig. S6 Weak interactions in the single crystal of TPE-OX: C-H N (green line), C-H π (orange line) and C-H O (red line).
Fig. S7 Weak interactions in the single crystal of pre-tpe-ox: C-H Br (green line), O-H Br (blue line), C-H π (orange line) and C-H O (red line). 1 H NMR and 13 C NMR spectra of pre-tpe-ox and TPE-OX 1 H NMR spectrum of pre-tpe-ox in CDCl 3.
13 C NMR spectrum of pre-tpe-ox in CDCl 3. 1 H NMR spectrum of TPE-OX in CDCl 3.
13 C NMR spectrum of TPE-OX in CDCl 3. References: S1. M. Banerjee, S. J. Emond, S. V. Lindeman and R. Rathore, J. Org. Chem., 2007, 72, 8054. S2. R. Hu, J. L. Maldonado, M. Rodriguez, C. Deng, C. K. W. Jim, J. W. Y. Lam, M. M. F. Yuen, G. Ramos-Ortiz and B. Z. Tang, J. Mater. Chem., 2011, 22, 232. S3. M. Inouye, M. Ueno, K. Tsuchiya, N. Nakayama, T. Konishi and T. Kitao, J. Org. Chem., 1992, 57, 5377. S4. Nakazaki, M.; Yamamoto, K., J. Org. Chem. 1976, 41, 1877. S5. L. E. Elizalde, R. Ledezma, and Raúl. G. López, Synthetic Communications, 2005, 35, 603.