2.2 Synthesis of chromophore ETO
Chromophore 1 (0.95 g, 1.0 mmol) was dissolved in 20 mL of THF. Aqueous solution of HCl (10 mL, 1 N) was added and the mixture was stirred at ambient temperature for 2 h. Then, the solvent was removed and the crude product was purified by flashchromatography over silica gel using 20% ethyl acetate in hexane as eluent affording chromophore 1-OH (0.79 g, 1.82 mmol). The yield was about 90%. 1H NMR (400 MHz, CD3COCD3),δ : 8.53 (d, J = 15.2 Hz, 1H), 7.78 (d, J = 8.0 Hz, 2H), 7.12 (d, J = 15. 6 Hz, 1H), 7.00 (d, J = 8.4 Hz, 2H), 6.44 (s, 1H), 6.42 (s, 2H), 5. 26 (s, 2H), 3.87 (t, J = 4.8 Hz, 4H), 3.86 (d, J = 5.2 Hz, 4H), 3.80 (t, J = 5.2 Hz, 4H) 1.64–1.68 (m, 2H), 1.28–1.49 (m, 16H), 0.87–0.90 (m, 12H). IR (KBr)ν: 3364, 2933, 2222, 1734, 1539, 1396, 1280, 1180 cm−1. MS (MALDI-TOF) m/z: 744 (M + Na+) calc. for C43H55N5O5: 721.42.
Compound 1-OH (0.36 g, 0.5 mmol) and anthracen-9-ylmethoxy-4-oxobutanoic acid (0.31 g, 1.0 mmol) were dissolved in 50 mL CH2Cl2. DMAP (0.12 g, 1.0 mmol) and DCC (0.21 g, 1.0 mmol) were added to the mother solution. The reaction solution was stirred at room temperature for 5 h under argon. Then, the result solution was poured into 100 mL water and extract with CH2Cl2. The resulting compound was purified by silica gel column chromatography (VEA:Vchloroform = 1:5) to give blue solid. Yield: 60%. 1H NMR (400 MHz, CDCl3): 8.47 (s, 2H), 8.45 (d, J = 16.0 Hz, 1H), 8.30 (d, J = 9.2 Hz, 4H), 8.00 (d, J = 8.4 Hz, 4H), 7.56 (t, J = 8.4 Hz, 4H), 7.47 (t, J = 7.24 Hz, 4H), 7.40 (d, J = 8.8 Hz, 2H), 7.03 (d, J = 15.2 Hz, 1H), 6.48 (d, J = 8.8 Hz, 2H), 6.39 (s, 1H), 6.29 (s, 2H), 6.16 (s, 4H), 5.23 (s, 2H), 4.02 (t, J = 6.0 Hz, 4H), 3.81 (d, J = 6.0 Hz, 4H), 3.30 (t, J = 5.6 Hz, 4H), 2.61 (t, J = 8.4 Hz, 4H), 2.56 (t, J = 6.4 Hz, 4H), 1.67–1.70 (m, 2H), 1.31–1.49 (m, 16H), 0.87–0.90 (m, 12H). IR (KBr),ν: 3327, 2928, 2220, 1734, 1533, 1178, 733 cm−1. MS (MALDI-TOF) m/z: 1324 (M + Na+), calc. for C80H82N5O11: 1302.55.
2.3 Synthesis of polymer PMMA-AMA
Methyl methacrylate(4 g, 40 mmol) and anthracen-9-ylmethyl methacrylate (2.76 g, 10 mmol) was dissolved in 50 ml 1,4-dioxacyclohexane. When all of the solid was dissolved, 2,2′-azobis(2,4-dimethyl)valeronitrile (0.05 g) was added to the solution. Nitrogen was introduced to the mixture for 0.5 h. Then the temperature was raised to 70 °C. And the temperature was kept for 8 h under the nitrogen atmosphere. The solution was slowly dropped into 500 mL ether and the white solid was precipitated. The solid was collected by filtration and washed for three times by methanol. Affording PMMA-AMA 6.12 g, yield: 90%. 1H NMR (400 MHz, CDCl3): 1H NMR (400 MHz, CDCl3): 8.76 (s, 1H), 8.10 (s, 4H), 7.68 (m, 4H), 4.68 (s, 24H), 3.59 (s, 12H), 2.15 (s, 10H), 1.68–1.83 (s, 15H).