3.2.2. General Procedures for 1-Alkyl-3-Methacryloyl (Acryloyl)-Benzimidazolone (Thione) (3)
With nitrogen protection, to a solution of 2 (1 mmol) in anhydrous dichloromethane (10 mL) was added triethylamine (0.3 mL, 2.1 mmol). Carboxylic chloride (1 mmol) in dichloromethane (2 mL) was added in an ice-water bath, and the mixture was stirred for 5 h at room temperature. Saturated NaHCO3 solution (10 mL) was added, and the mixture was extracted by dichloromethane (3 × 15 mL). The organic extracts were combined, washed with water and saturated NaCl solution in that order, dried over Na2SO4, and finally concentrated under vacuum. After purification on a silica gel column, target compounds were obtained.
1-ethyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI1): white crystalline solid (0.145 g, 63% yield), mp 60–62 °C. 1H-NMR (500 MHz, CDCl3) δ 1.36 (t, J = 7.0 Hz, 3H), 2.15 (s, 3H), 3.91 (q, J = 7.0 Hz, 2H), 5.54 (s, 1H), 5.55 (s, 1H), 7.01 (d, J = 8.0 Hz, 1H), 7.16 (t, J = 8.0 Hz, 1H), 7.22–7.26 (m, 1H), 7.97 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.1, 19.0, 36.0, 107.7, 115.0, 121.2, 122.4, 124.5, 126.6, 129.9, 140.7, 151.2, 170.4. ESI-MS: 231.1153 ([M+H]+, [C13H14N2O2+H]+; calc. 231.1134).
1-propyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI2): white crystalline solid (0.136 g, 56% yield), mp 67–68 °C. 1H-NMR (500 MHz, CDCl3) δ 0.99 (t, J = 7.0 Hz, 3H), 1.76–1.81 (m, 2H), 2.14 (s, 3H), 3.81 (t, J = 7.0 Hz, 2H), 5.53 (s, 1H), 5.55 (s, 1H), 7.00 (d, J = 8.0 Hz, 1H), 7.15 (t, J = 8.0 Hz, 1H),7.21–7.26 (m, 1H), 7.96 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 11.3, 18.9, 21.3, 42.8, 107.8, 114.9, 121.2, 122.4, 124.4, 126.5, 130.4, 140.7, 151.6, 170.4. ESI-MS: 245.1295 ([M+H]+, [C14H16N2O2+H]+; calc. 245.1290).
1-isopropyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI3): yellow oil (0.158 g, 65% yield). 1H-NMR (500 MHz, CDCl3) δ 1.53 (d, J = 6.0 Hz, 6H), 2.14 (s, 3H), 4.62–4.64 (m, 1H), 5.52(s, 1H), 5.54 (s, 1H), 7.11 (d, J = 8.0 Hz, 1H), 7.18–7.23 (m, 2H), 7.96 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.9, 21.7 (2CH3), 45.4, 108.9, 114.8, 121.0, 122.7, 124.3, 126.6, 129.3, 140.9, 150.9, 170.4. ESI-MS: 245.1280 ([M+H]+, [C14H16N2O2+H]+; calc. 245.1290).
1-isobutyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI4): white solid (0.142 g, 55% yield), mp 55–56 °C. 1H-NMR (500 MHz, CDCl3) δ 0.98 (d, J = 5.0 Hz, 6H), 2.14 (s, 3H), 2.19–2.22 (m, 1H), 3.64 (d, J = 6.5, 2H), 5.53 (s, 1H), 5.55 (s, 1H), 6.98 (d, J = 8.0 Hz, 1H), 7.13–7.26 (m, 2H), 7.96 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.9, 20.2 (2CH3), 27.6, 48.6, 108.1, 114.8, 121.3, 122.4, 124.4, 126.5, 130.7, 140.7, 151.8, 170.4. ESI-MS: 259.1455 ([M+H]+, [C15H18N2O2+H]+; calc. 259.1447).
1-pentyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI5): white solid (0.166 g, 61% yield), mp 72–73 °C. 1H-NMR (500 MHz, CDCl3) δ 0.90 (CH3, br.s, 3H), 1.36 (2CH2, br.s, 4H), 1.75–1.76 (m, 2H), 2.14 (s, 3H), 3.83 (t, J = 7.0 Hz, 2H), 5.54 (s, 1H), 5.55 (s, 1H), 6.98 (d, J = 8.0 Hz, 1H), 7.06–7.23 (m, 2H), 7.96 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.9, 18.9, 22.3, 27.5, 28.9, 41.2, 107.8, 114.9, 121.2, 122.4, 124.4, 126.6, 130.3, 140.7, 151.5, 170.4. ESI-MS: 273.1629 ([M+H]+, [C16H20N2O2+H]+; calc. 273.1603).
1-allyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI6): white solid (0.140 g, 58% yield), mp 42–44 C. 1H-NMR (500 MHz, CDCl3) δ 2.14 (s, 3H), 4.46 (d, J = 5.5 Hz, 2H), 5.26–5.29 (m, 2H), 5.54 (s, 1H), 5.56 (s, 1H), 5.85–5.92 (m, 1H), 6.98 (d, J = 8.0 Hz, 1H), 7.14–7.26 (m, 2H), 7.96 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.9, 43.5, 108.4, 114.9, 118.4, 121.3, 122.6, 124.5, 126.5, 130.1, 131.0, 140.6, 151.3, 170.3. ESI-MS: 243.1139 ([M+H]+, [C14H14N2O2+H]+; calc. 243.1134).
1-benzyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-one (3aI7): white solid (0.188 g, 64% yield), mp 112–114 °C. 1H-NMR (500 MHz, CDCl3) δ 2.14 (s, 3H), 5.04 (s, 2H), 5.54 (s, 1H), 5.56 (s, 1H), 6.89–6.92 (m, 1H), 7.14–7.16 (m, 2H), 7.24–7.34 (m, 5H), 8.22–8.25 (m, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.9, 44.8, 108.3, 116.2, 122.7, 124.6, 126.5, 127.5(2C), 128.1, 129.2(2C), 129.9, 132.0, 135.2, 140.5, 151.7, 170.3. ESI-MS: 293.1289 ([M+H]+, [C18H16N2O2+H]+; calc. 293.1290).
1-ethyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII1): white crystalline solid (0.117 g, 54% yield), mp 45–47 °C. 1H-NMR (500 MHz, CDCl3) δ 1.36 (t, J = 7.0 Hz, 3H), 3.92 (q, J = 7.0 Hz, 2H), 5.98 (d, J = 11.0 Hz, 1H), 6.67 (d, J = 17.0 Hz, 1H), 6.99 (d, J = 8.0 Hz, 1H), 7.14–7.26 (m, 2H), 7.79 (dd, J = 17.0 Hz, 11.0 Hz, 1H), 8.24 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.1, 36.0, 107.5, 116.1, 122.7, 124.7, 126.6, 129.2, 129.7, 131.8, 151.9, 165.3. ESI-MS: 217.0980 ([M+H]+, [C12H12N2O2+H]+; calc. 217.0977).
1-propyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII2): white solid (0.115 g, 50% yield), mp 66–67 °C. 1H-NMR (500 MHz, CDCl3) δ 1.00 (t, J = 7.0 Hz, 3H), 1.80 (q, J = 7.0 Hz, 2H), 3.83 (t, J = 7.0 Hz, 2H), 5.98 (d, J = 10.0 Hz, 1H), 6.67 (d, J = 17.0 Hz, 1H), 6.99 (d, J = 7.5 Hz, 1H), 7.14–7.26 (m, 2H), 7.79 (dd, J = 17.0 Hz, 10.0 Hz, 1H), 8.24 (d, J = 7.5 Hz, 1H); 13C NMR (125 MHz, CDCl3) δ 11.3, 21.2, 42.8, 107.7, 116.1, 122.7, 124.7, 126.5, 129.3, 130.2, 131.8, 152.3, 165.4. ESI-MS: 231.1139 ([M+H]+, [C13H14N2O2+H]+; calc. 231.1134).
1-isopropyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII3): white solid (0.138 g, 60% yield), mp 93–95 °C. 1H-NMR (500 MHz, CDCl3) δ 1.56 (d, J = 5.0 Hz, 6H), 4.68–4.70 (m, 1H), 5.97 (d, J = 10.0 Hz, 1H), 6.65 (d, J = 16.5 Hz, 1H), 7.13–7.26 (m, 2H), 7.76 (dd, J = 16.5 Hz, 10.0 Hz, 1H), 8.25 (d, J = 7.5 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 19.8, 45.4, 108.8, 116.1, 122.3, 124.4, 126.7, 129.1, 129.5, 131.6, 151.6, 165.5. ESI-MS: 231.1130 ([M+H]+, [C13H14N2O2+H]+; calc. 231.1134).
1-isobutyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII4): white solid (0.151 g, 62% yield), mp 106–108 °C. 1H-NMR (500 MHz, CDCl3) δ 1.00 (d, J = 5.0 Hz, 6H), 2.21–2.23 (m, 1H), 3.66 (d, J = 6.0 Hz, 2H), 5.98 (d, J = 10.5 Hz, 1H), 6.67 (d, J = 17.0 Hz, 1H), 6.97 (d, J = 7.5 Hz, 1H), 7.14–7.26 (m, 2H), 7.79 (dd, J = 16.0 Hz, 11.0 Hz, 1H), 8.23 (d, J = 7.5 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 20.2(2CH3), 27.6, 48.6, 107.9, 116.0, 122.6, 124.6, 126.5, 129.3, 130.5, 131.8, 152.5, 165.4. ESI-MS: 245.1291 ([M+H]+, [C14H16N2O2+H]+; calc. 245.1290).
1-pentyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII5): white solid (0.163 g, 63% yield), mp 54–56 °C. 1H-NMR (500 MHz, CDCl3) δ 0.89 (t, J = 6.0 Hz, 3H), 1.34–1.36(m, 4H), 1.70–1.73 (m, 2H), 3.78 (t, J = 7.5 Hz, 2H), 5.93 (dd, J = 10.5, 1.5 Hz, 1H), 6.63 (dd, J = 1.5, 17.0 Hz, 1H), 6.91 (d, J = 8.0 Hz, 1H), 7.04–7.17 (m, 2H), 7.78 (dd, J = 10.5 Hz, 17.0 Hz, 1H), 8.15 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.9, 22.3, 27.5, 28.9, 41.0, 107.5, 115.8, 122.4, 124.5, 126.4, 129.3, 130.0, 131.4, 152.0, 165.0. ESI-MS: 259.1450 ([M+H]+, [C15H18N2O2+H]+; calc. 259.1447).
1-allyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII6): yellow oil (0.135 g, 59% yield). 1H-NMR (500 MHz, CDCl3) δ 4.49–4.50 (d, J = 4.0 Hz, 2H), 5.25–5.29 (m, 2H), 5.87–5.92 (m, 1H), 5.99 (d, J = 10.0 Hz, 1H), 6.68 (d, J = 17.0 Hz, 1H), 6.97 (d, J = 8.0 Hz, 1H), 7.14–7.26 (m, 2H), 7.79 (dd, J = 17.0 Hz, 10.0 Hz, 1H), 8.24 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 43.4, 108.2, 116.0, 118.3, 122.9, 124.7, 126.5, 129.2, 129.9, 130.9, 132.0, 152.0, 165.3. ESI-MS: 229.0980 ([M+H]+, [C13H12N2O2+H]+; calc. 229.0977).
1-benzyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-one (3aII7): white solid (0.206 g, 74% yield), mp 118–119 °C. 1H-NMR (500 MHz, CDCl3) δ 5.05 (s, 2H), 6.01 (dd, J = 10.0, 1.5 Hz, 1H), 6.69 (dd, J = 17.5, 1.5 Hz, 1H), 6.89–6.91 (m, 1H), 7.13–7.16 (m,2H), 7.26–7.34 (m, 5H), 7.83 (dd, J = 10.0, 1.5 Hz, 1H), 8.23–8.25 (m, 1H). 13C-NMR (125 MHz, CDCl3) δ 44.9, 108.3, 116.1, 122.9, 124.8, 126.5, 127.5(2C), 128.1, 129.0(2C), 129.2, 129.9, 132.0, 135.2, 152.5, 165.3. ESI-MS: 279.1133 ([M+H]+, [C17H14N2O2+H]+; calc. 279.1134).
1-ethyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI1): white solid (0.128 g, 52% yield), mp 38–39 °C. 1H-NMR (500 MHz, CDCl3) δ 1.44 (t, J = 7.5 Hz, 3H), 2.19 (s, 3H), 3.33 (q, J = 7.5 Hz, 2H), 5.70 (s, 1H), 5.82 (s, 1H), 7.20–7.29 (m, 2H), 7.59 (d, J = 8.0 Hz, 1H), 7.63 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 14.0, 18.6, 27.4, 113.4, 118.5, 123.2, 124.3, 126.1, 134.1, 139.3, 143.9, 154.4, 169.1. ESI-MS: 247.0900 ([M+H]+, [C13H14N2OS+H]+; calc. 247.0905).
1-propyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI2): yellow oil (0.158 g, 61% yield). 1H-NMR (500 MHz, CDCl3) δ 1.07 (t, J = 7.0 Hz, 3H), 1.81 (q, J = 7.0 Hz, 2H), 2.18 (s, 3H), 3.30 (t, J = 7.0 Hz, 2H), 5.68 (s, 1H), 5.80 (s, 1H), 7.18 (t, J = 7.5, 1H), 7.25 (t, J = 7.5, 1H), 7.57 (d, J = 7.5 Hz, 1H), 7.61 (d, J = 7.5 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.5, 18.5, 22.2, 35.0, 113.4, 118.5, 123.2, 124.2, 126.1, 134.1, 139.3, 143.9, 154.5, 169.0. ESI-MS: 261.1063 ([M+H]+, [C14H16N2OS+H]+; calc. 261.1062).
1-isopropyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI3): yellow oil (0.148 g, 57% yield). 1H-NMR (500 MHz, CDCl3) δ 1.46 (d, J = 6.5 Hz, 6H), 2.17 (s, 3H), 4.13–4.15 (m, 1H), 5.66 (s, 1H), 5.79 (s, 1H), 7.18–7.27 (m, 2H), 7.57 (d, J = 8.0 Hz, 1H), 7.62 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.5, 23.0(2CH3), 39.1, 113.3, 118.5, 123.3, 124.2, 126.3, 133.9, 139.4, 143.9, 153.8, 169.1. ESI-MS: 261.1063 ([M+H]+, [C14H16N2OS+H]+; calc. 261.1062).
1-isobutyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI4): white solid (0.176 g, 64% yield), mp 55–57 °C. 1H-NMR (500 MHz, CDCl3) δ 1.07 (d, J = 5.0 Hz, 6H), 2.04–2.06 (m, 1H), 2.19 (s, 3H), 3.24 (d, J = 5.0 Hz, 2H), 5.69 (s, 1H), 5.82 (s, 1H), 7.18–7.28 (m, 2H), 7.57 (d, J = 8.0 Hz, 1H), 7.62 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 18.5, 22.1, 28.1, 41.6, 113.3, 118.5, 123.2, 124.2, 126.2, 134.2, 139.3, 143.8, 154.8, 169.1. ESI-MS: 275.1213 ([M+H]+, [C15H18N2OS+H]+; calc. 275.1218).
1-pentyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI5): yellow oil (0.196 g, 68% yield). 1H-NMR (500 MHz, CDCl3) δ 0.91 (d, J = 7.5 Hz, 3H), 1.33–1.47 (m, 4H), 1.74–1.78 (m, 2H), 2.16 (s, 3H), 3.31 (t, J = 7.5 Hz, 2H), 5.66 (s, 1H), 5.77 (s, 1H), 7.14–7.25 (m, 2H), 7.55 (d, J = 8.0 Hz, 1H), 7.60 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.9, 18.5, 22.2, 28.4, 31.0, 33.0, 113.4, 118.5, 123.1, 124.2, 126.0, 134.1, 139.2, 143.9, 154.5, 168.9. ESI-MS: 289.1373 ([M+H]+, [C16H20N2OS+H]+; calc. 289.1375).
1-allyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI6): colorless oil (0.137g, 53% yield). 1H-NMR (500 MHz, CDCl3) δ 2.16 (s, 3H), 3.97 (d, J = 7.5 Hz, 2H), 5.16 (d, J = 10.5, 1H), 5.35 (dd, J = 17.0, 1.0 Hz, 1H), 5.67 (s, 1H), 5.78 (s, 1H), 5.98–6.06 (m, 1H), 7.16–7.26 (m, 2H), 7.57 (d, J = 8.0 Hz, 1H), 7.60 (d, J = 8.0 Hz, 1H); 13C-NMR (125 MHz, CDCl3) δ 13.9, 18.5, 22.2, 28.4, 31.0, 33.0, 113.4, 118.5, 123.1, 124.2, 126.0, 134.1, 139.2, 143.9, 154.5, 168.9. ESI-MS: 259.0503 ([M+H]+, [C14H14N2OS+H]+; calc. 259.0509).
1-benzyl-3-methacryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bI7): colorless oil (0.215g, 69% yield). 1H-NMR (500 MHz, CDCl3) δ 2.16 (s, 3H), 4.57 (s, 2H), 5.68 (s, 1H), 5.79 (s, 1H), 7.20–7.34 (m, 5H), 7.43–7.45 (m, 2H), 7.60 (d, J = 8.0, 1H), 7.66 (d, J = 8.0, 1H). 13C-NMR (125 MHz, CDCl3) δ 18.6, 37.8, 113.5, 118.6, 123.4, 124.4, 126.1, 127.7, 128.7(2C), 129.4(2C), 134.1, 136.2, 139.2, 143.8, 154.1, 168.9. ESI-MS: 309.1065 ([M+H]+, [C18H16N2OS+H]+; calc. 309.1062).
1-ethyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII1): white solid (0.132 g, 57% yield), mp 82–83 °C. 1H-NMR (500 MHz, CDCl3) δ 1.48 (t, J = 7.5 Hz, 3H), 3.36 (q, J = 7.5 Hz, 2H), 6.16 (d, J = 10.5 Hz, 1H), 6.73 (d, J = 17.0 Hz, 1H), 7.04–7.10 (dd, J = 17.0, 10.5 Hz, 1H), 7.23–7.33 (m, 2H), 7.63–7.66 (m, 2H),; 13C-NMR (125 MHz, CDCl3) δ 13.9, 27.0, 113.4, 118.8, 123.3, 124.6, 129.4, 133.2, 133.8, 144.2, 154.7, 164.4. ESI-MS: 233.0743 ([M+H]+, [C12H12N2OS+H]+; calc. 233.0749).
1-propyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII2): white solid (0.160 g, 65% yield), mp 100–102 °C. 1H-NMR (500 MHz, CDCl3) δ 1.08 (t, J = 7.5 Hz, 3H), 1.83–1.85 (m, 2H), 3.42 (q, J = 7.5 Hz, 2H), 6.16 (d, J = 10.5 Hz, 1H), 6.73 (d, J = 17.0 Hz, 1H), 7.07 (dd, J = 17.0, 10.5 Hz, 1H), 7.23–7.33 (m, 2H), 7.63–7.66 (m, 2H),; 13C-NMR (125 MHz, CDCl3) δ 13.4, 22.7, 38.8, 113.5, 118.7, 123.3, 124.6, 129.5, 133.3, 133.7, 144.1, 154.9, 164.4. ESI-MS: 247.0910 ([M+H]+, [C13H14N2OS+H]+; calc. 247.0905).
1-isopropyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII3): white solid (0.130 g, 53% yield), mp 102–103 °C. 1H-NMR (500 MHz, CDCl3) δ 1.51 (d, J = 6.0 Hz, 6H), 4.18–4.20 (m, 1H), 6.15 (d, J = 10.5, 1H), 6.72 (d, J = 17.0, 1H), 7.07 (dd, J = 17.0, 10.5 Hz, 1H), 7.23–7.26 (m, 1H), 7.29–7.32 (m, 1H), 7.64–7.66 (m, 2H); 13C-NMR (125 MHz, CDCl3) δ 23.0 (2CH3), 37.8, 113.5, 118.7, 123.3, 124.5, 129.6, 133.1, 133.6, 144.3, 154.1, 164.4. ESI-MS: 247.0910 ([M+H]+, [C13H14N2OS+H]+; calc. 247.0905).
1-isobutyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII4): colorless oil (0.153 g, 59% yield). 1H-NMR (500 MHz, CDCl3) δ 1.10 (d, J = 6.0 Hz, 6H), 2.08–2.10 (m, 1H), 3.28 (d, J = 6.0 Hz, 2H), 6.13 (d, J = 10.5, 1H), 6.69 (d, J = 17.0, 1H), 7.06 (dd, J = 17.0, 10.5 Hz, 1H), 7.21–7.28 (m, 2H), 7.59–7.62 (m, 2H); 13C-NMR (125 MHz, CDCl3) δ 22.2 (2CH3), 28.0, 41.1, 113.5, 118.7, 123.3, 124.5, 129.5, 133.3, 133.7, 144.1, 155.0, 164.4. ESI-MS: 261.1050 ([M+H]+, [C14H16N2OS+H]+; calc. 261.1062).
1-pentyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII5): colorless oil (0.186 g, 64% yield). 1H-NMR (500 MHz, CDCl3) δ 0.88 (t, J = 6.0 Hz, 3H), 1.35–1.38 (m, 4H), 1.77–1.80 (m, 2H), 3.53 (t, J = 7.5 Hz, 2H), 6.14 (d, J = 10.5), 6.70 (d, J = 17.0 Hz, 1H), 7.04 (dd, J = 17.0,10.5 Hz, 1H), 7.22–7.29 (m, 2H), 7.60–7.62 (m, 2H); 13C-NMR (125 MHz, CDCl3) δ 14.0, 22.2, 28.0, 29.0, 38.7, 113.6, 118.8, 123.3, 124.6, 129.4, 133.2, 133.7, 144.1, 152.0, 164.4. ESI-MS: 275.1211 ([M+H]+, [C15H18N2OS+H]+; calc. 275.1218).
1-allyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII6): white solid (0.161 g, 66% yield), mp 104–106 °C. 1H-NMR (500 MHz, CDCl3) δ 4.02 (d, J = 7.0 Hz, 2H), 5.15 (d, J = 10.0 Hz, 1H), 5.36 (dd, J = 16.5 Hz, 1H), 6.04–6.07 (m, 1H), 6.16 (d, J = 10.5, 1H), 6.72 (d, J = 17.0 Hz, 1H), 7.05 (dd, J = 17.0, 10.5 Hz, 1H), 7.22–7.29 (m, 2H), 7.60–7.62 (m, 2H); 13C-NMR (125 MHz, CDCl3) δ 35.5, 113.4, 119.1, 123.4, 124.6, 129.3, 132.6, 133.9, 143.5, 154.2, 164.3. ESI-MS: 245.0741 ([M+H]+, [C13H12N2OS+H]+; calc. 245.0749).
1-benzyl-3-acryloyl-1H-benzo[d]imidazol-2(3H)-thione (3bII7): colorless oil (0.223 g, 76% yield). 1H-NMR (500 MHz, CDCl3) δ 4.56 (s, 2H), 6.00 (dd, J = 10.0, 1.5 Hz, 1H), 6.68 (dd, J = 17.5, 1.5 Hz, 1H), 6.89–6.91 (m, 1H), 7.13–7.15 (m,2H), 7.27–7.34 (m, 5H), 7.83 (dd, J = 10.0, 1.5 Hz, 1H), 8.24–8.26(m, 1H). 13C-NMR (125 MHz, CDCl3) δ 37.9, 113.6, 119.1, 123.5, 124.7, 127.5(2C), 128.1, 129.1(2C), 129.3, 133.0, 133.9, 135.4, 143.8, 154.1, 164.5. ESI-MS: 295.0902 ([M+H]+, [C17H14N2OS+H]+; calc. 295.0905).