图共 10个 表共 4
    • 图  FIG. 430.  FIG. 430.

      Figure FIG. 430..  FIG. 430.

    • 图  1  目标分子1a1p以及2o2c的合成路线

      Figure 1.  Synthetic route of target molecules 1a and 1p as well as 2o and 2c

    • 图  2  目标化合物1在C6D6中的1H-NMR谱(400 MHz, 293 K)

      Figure 2.  1H-NMR spectra (400 MHz, 293 K) of target compound 1 in C6D6

    • 图  3  目标化合物2在tetrahydrofuran-d8中的1H-NMR谱(400 MHz, 293 K)

      Figure 3.  1H-NMR spectra (400 MHz, 293 K) of compound 2 in tetrahydrofuran-d8

    • 图  4  目标化合物3在氘代四氢呋喃中的1H-NMR谱(400 MHz, 293 K)

      Figure 4.  1H-NMR spectra (400 MHz, 293 K) of compound 3 in tetrahydrofuran -d8

    • 图  5  目标化合物4在氘代四氢呋喃中的1H-NMR谱(400 MHz, 293 K)

      Figure 5.  1H-NMR spectra (400 MHz, 293 K) of compound 4 in tetrahydrofuran -d8

    • 图  6  (a) 1a、(b) 2o、(c) 3a和(d) 4o的四氢呋喃溶液在紫外光(λ = (313 ± 10) nm)照射下吸收和荧光光谱的变化。荧光的激发波长分别为(a) 361 nm、(b) 366 nm、(c) 309 nm和(d) 323 nm。插图展示了颜色和荧光在紫外光(λ = (313 ± 10) nm)和可见光(λ > 470 nm)照射下的变化。图中箭头向上和向下分别表示受到光照后光谱上升或下降的趋势

      Figure 6.  Absorption and fluorescence changes of (a) 1a, (b) 2o, (c) 3a, and (d) 4o in tetrahydrofuran upon UV irradiation at (313 ± 10) nm. Excitation for fluorescence is set at (a) 361 nm, (b) 366 nm, (c) 309 nm and (d) 323 nm, respectively. Inset images show the color and emission changes triggered by UV (λ = (313 ± 10) nm) and visible (λ > 470 nm) light. The arrows up and down indicate the increase and decrease tendency of the spectra upon irradiation by light, respectively

    • 图  7  (a) 1a1p (2.09 × 10−5 mol/dm3)和(b) 3a3p (2.14 × 10−5 mol/dm3)在四氢呋喃溶液中紫外可见吸收和荧光光谱对比。插图为1p3p在紫外光(λ = (313 ± 10) nm,0.21 mW/cm2,6 min)照射前后的变化

      Figure 7.  UV-vis absorption and fluorescence spectra of (a) 1a and 1p (2.09 × 10−5 mol/dm3) and (b) 3a and 3p (2.14 × 10−5 mol/dm3) in tetrahydrofuran. Insert images show spectra changes of 1p and 3p upon irradiation by UV light (λ = (313 ± 10) nm, 0.21 mW/cm2) for 6 min

    • 图  8  293 K下目标化合物1c(a)和3c(b)在不同溶剂中的衰减曲线

      Figure 8.  Decay curves of compound 1c(a) and 3c(b) in different solvents at 293 K

    • 图  9  目标化合物1~4闭环体在乙腈中的热稳定性对比

      Figure 9.  Comparison of the thermal stability of closed form of target compounds 1~4 in acetonitrile

    • Open formClosed form
      ap-Conformerp-Conformer

      表 1  目标化合物1~4的开环体的平行与反平行异构体和闭环体的化学结构式

      Table 1.  Chemical structures of parallel and anti-parallel conformer of open form as well as closed form of the target compounds 1~4

    • Compoundλmaxa)/nmεmax/(103 mol−1·dm3·cm−1)λema) /nmΦo-cb) /%Φc-ob) /%CRc) /%
      1a29648.85195698
      1p29152.5482
      1c5617.011.2>99
      2o29455.04803497
      2c64910.30.1d)>99
      3a28853.760068>99
      3p28757.2590
      3c5699.56519.0>99
      4o29559.258432>99
      4c65411.81.1>99
      a) Typical absorption (λmax) and emission maxima (λem) of o-form in UV region and c- form in the visible region, respectively; b) Quantum yields of photocyclization (Φo-c) at 313 nm and cycloreversion (Φc-o) at 517 nm; c) Conversion ratio (CR) from o- to c- form (irradiation at λ = 313 nm) or from c- to o- form (irradiation at λ > 470 nm); d) Quantum yields of cycloreversion (Φc-o) at 562 nm

      表 2  目标化合物1~4在四氢呋喃溶液中的光谱数据

      Table 2.  Spectroscopic data of compound 1~4 in tetrahydrofuran solution

    • Solventτ1/2/sk/10−5 s−1A0
      Cyclohexane2 33629.710.829 7
      Toluene1 34451.780.452 9
      Tetrahydrofuran918.673.780.863 1
      Methylene chloride722.593.890.732 1
      Acetonitrile393.2174.00.767 9
      Methanol371.0186.10.817 3

      表 3  293 K下目标化合物1c在不同溶剂中的热衰减动力学数据

      Table 3.  Spectrokinetic data of thermal decay for compound 1c in various solvents at 293 K

    • Solventτ1/2/sk /10−5 s−1A0
      Toluene53 6481.2920.629 6
      Tetrahydrofuran53 2131.3020.669 7
      Acetonitrile35 3891.9580.592 0

      表 4  293 K下目标化合物3c在不同溶剂中的热衰减动力学数据

      Table 4.  Spectrokinetic data of thermal decay for compound 3c in various solvents at 293 K