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2
M ATERIALS AND M ETHODS
This context includes the published contents:
1. Deok-Ho Roh†, Kwang Min Kim†, Jung Seung Nam, Un-Young Kim, Byung-Man Kim, Jeong Soo Kim, and Tae-Hyuk Kwon* J. Phys. Chem. C 2016, 120, 24655–24666. DOI:
10.1021/acs.jpcc.6b08262. Reproduced with permission of Copyright © 2016 American Chemical Society.
2. Deok-Ho Roh†, Jun-Hyeok Park†, Hyun-Gyu Han†, Ye-Jin Kim†, Daiki Motoyoshi, Eunhye Hwang, Wang-Hyo Kim, Joseph I. Mapley, Keith C. Gordon, Shogo Mori*, Oh-Hoon Kwon*, and Tae-Hyuk Kwon* Chem. 2022, 8, 1121–1136. DOI: 10.1016/j.chempr.2022.01.017. Reproduced with permission of Copyright © 2022 Elsevier.
3. Deok-Ho Roh†, HyeonOh Shin†, Hyun-Tak Kim†, and Tae-Hyuk Kwon* ACS Appl. Mater.
Interfaces. 2021, 13, 61598–61609. DOI: 10.1021/acsami.1c13755. Reproduced with permission of Copyright © 2021 American Chemical Society.
2.1.SYNTHESIS AND CHARACTERIZATION OF ORGANIC MATERIALS
2.1.1. Photosensitizers
3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-(2H,5H)-dione (2). In a dried Schlenk round-bottom flask (RBF), elemental sodium (3.18 g, 138.26 mmol) was added to tert-amyl alcohol (75 mL), and the mixture was stirred at 110 °C until complete dissolution. The temperature was decreased to 90 °C and 2-thiophenecarbonitrile (6.67 mL, 71.53 mmol) was added in one portion, affording a brown medium.
A solution of diethyl succinate (4.8 mL, 28.66 mmol) in 2-methylbutan-2-ol (18 mL) was added drop by drop, and the mixture was further stirred overnight at 110 °C. Acetic acid (AcOH, 20 mL) solution diluted with methanol (120 mL) was injected to the medium and further stirred for 120 min at 110 °C, resulting the precipitation of solid, obtained by filtration method. Several washes the precipitation with methanol (200 mL) were carried out for purification. The pure solid was dried to give a purple powder (7.67 g, 25.54 mmol, 90%). 1H NMR (400 MHz, DMSO-d6): 11.25 (s, 2H), 8.21 (dd, J = 4.0, 1.2 Hz, 2H), 7.97 (dd, J = 4.8, 1.2 Hz, 2H), 7.3 (dd, J = 5.0, 4.0 Hz, 2H).
2,5-bis(2-ethylhexyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-dione (3). Compound 2 (6.0 g, 19.98 mmol) and K2CO3 (8.3 g, 59.98 mmol) were added in a 250 mL RBF under Ar atmosphere. A degassed anhydrous solution of DMF (100 mL) were injected to the mixture. The reaction solution was heated for 60 min at 120 °C. 2-ethylhexyl bromide (10.3 mL, 59.98 mmol) was then added dropwise.
The mixture was further heated overnight at 130 °C. After cool down to room temperature (RT), the resulting solution was diluted with CHCl3 (200 mL) and washed with H2O (5 × 200 mL). The CHCl3
layer was collected and concentrated via rotary evaporator. The mixture compound was purified by chromatography using a single solvent (CH2Cl2) to afford compound 3 (8.6 g, 16.38 mmol, 82%) as brown solid. 1H NMR (400 MHz, chloroform-d1): 8.90 (dd, J = 3.6, 1.2 Hz, 2H), 7.63 (dd, J = 5.2, 1.2 Hz, 2H), 7.27 (dd, J = 5.2, 4.0 Hz, 2H), 4.03 (m, 4H), 1.86 (m, 2H), 1.38–1.22 (m, 16H), 0.89–0.83 (m, 12H).
3-(5-bromothiophen-2-yl)-bis(2-ethylhexyl)-6-(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-dione (4).
To a suspension of compound 3 (1.0 g, 1.906 mmol) in CHCl3 (190 mL) at 0 °C was added NBS (339 mg, 1.906 mmol) under Ar atmosphere. The mixture was stirred at 0 °C followed by slowly up to RT overnight under the absence of light. The resulting solution was diluted with CHCl3 (120 mL) and washed with H2O (2 × 200 mL). The CHCl3 layer was collected and concentrated via rotary evaporator.
The remaining mixture was purified by chromatography using Hex/CHCl3 (v/v = 3:1) mixture to afford compound 4 (560 mg, 0.928 mmol, 49%) as brown solid. 1H NMR (400 MHz, chloroform-d1): 8.90 (d, 1H), 8.62 (d, 1H), 7.64 (d, 1H), 7.26 (d, 1H), 7.23 (d, 1H), 4.02–3.94 (m, 4H), 1.84 (m, 2H), 1.31–1.25 (m, 16H), 0.87 (m, 12H).
4-(5-(bis(2-ethylhexyl)-3,6-dioxo-4-(thiophen-2-yl)-2,3,5,6-tetrahydropyrrolo[3,4-
c]pyrrolyl)thiophen-2-yl)benzaldehyde (5a).1 Compound 4 (400 mg, 0.663 mmol), 4- formylphenylboronic acid (199 mg, 1.325 mmol), and Pd(PPh3)4 (38 mg, 0.033 mmol) were added in a 50 mL RBF under Ar atmosphere. A degassed solution of THF (22 mL) and 2 M K2CO3 (1.3 mL) were injected to the reaction solution. The mixture was heated at 65 °C overnight. After cooling to RT, the mixture was diluted with CH2Cl2 (100 mL) and washed with H2O (2 × 100 mL). The CH2Cl2 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 5a (400 mg, 0.636 mmol, 96%) as dark purple solid. 1H NMR (400 MHz, chloroform-d1): 10.04 (s, 1H), 8.94 (d, J = 4.0 Hz, 1H), 8.93 (dd, J = 3.6, 1.2 Hz, 1H), 7.95 (dd, J = 6.4, 2.0 Hz, 2H), 7.84 (dd, J = 6.4, 2.0 Hz, 2H), 7.66 (dd, J = 5.2, 1.2 Hz, 1H), 7.60 (d, J = 4.0 Hz, 1H), 7.29 (t, J = 5.2 Hz, 1H), 4.06 (m, 4H), 1.90 (m, 2H), 1.38–1.25 (m, 16H), 0.92–0.83 (m, 12H).
4-(5-(bis(2-ethylhexyl)-3,6-dioxo-4-(thiophen-2-yl)-2,3,5,6-tetrahydropyrrolo[3,4-
c]pyrrolyl)thiophen-2-yl)-3-methylbenzaldehyde (5b). Compound 4 (500 mg, 0.828 mmol), 4-formyl- 2-methylphenylboronic acid (272 mg, 1.657 mmol), and Pd(PPh3)4 (48 mg, 0.041 mmol) were added in a 50 mL RBF under Ar atmosphere. A degassed solution of THF (25 mL) and 2 M K2CO3 (1.7 mL) were injected to the reaction solution. The mixture was heated at 65 °C overnight. After cooling to RT, the resulting mixture was diluted with CH2Cl2 (100 mL) and washed with H2O (2 × 100 mL). The
by chromatography using a single solvent (CHCl3) to afford compound 5b (444 mg, 0.691 mmol, 83%) as dark purple powder. 1H NMR (400 MHz, chloroform-d1): 10.04 (s, 1H), 8.96 (d, J = 4.0 Hz, 1H), 8.93 (dd, J = 3.6, 1.2 Hz, 1H), 7.82 (bs, 1H), 7.78 (dd, J =8.0, 1.2 Hz, 1H), 7.65 (dd, J = 5.2, 1.2 Hz, 2H), 7.36 (d, J = 4.0 Hz, 1H), 7.29 (dd, J = 5.2, 4.0 Hz, 1H), 4.05 (m, 4H), 2.60 (s, 3H), 1.92–1.85 (m, 2H), 1.38–1.25 (m, 16H), 0.92–0.83 (m, 12H). 13C NMR (100 MHz, chloroform-d1): 191.72, 161.77, 161.68, 146.73, 140.68, 139.73, 138.78, 136.93, 135.90, 135.67, 135.52, 132.38, 130.79, 130.60, 129.77, 128.86, 128.50, 127.50, 108.40, 107.99, 45.95, 45.90, 39.29, 39.07, 30.27, 30.24, 30.20, 30.18, 29.69, 28.48, 28.33, 23.56, 23.51, 23.09, 23.06, 21.48, 14.05, 14.03, 10.49. FTIR (neat, cm−1): 3080, 2956, 2925, 2870, 2856, 2721, 1697, 1660, 1600, 1555, 1453, 1401, 1380, 1316, 1296, 1231, 1162, 1100, 1067, 1026, 858, 817, 776, 753, 713. HRMS (LC/Q-TOF) calc. for C38H47N2O3S2 = 643.3023. Found:
m/z = 643.3033 [(M+H)+]. Mass error = 1.54 ppm.
4-(5-(bis(2-ethylhexyl)-3,6-dioxo-4-(thiophen-2-yl)-2,3,5,6-tetrahydropyrrolo[3,4-
c]pyrrolyl)thiophen-2-yl)-3,5-dimethylbenzaldehyde (5c). Compound 4 (1.5 g, 2.485 mmol), 4-formyl- 2,6-dimethylphenylboronic acid (530 mg, 2.982 mmol), Pd2(dba)3 (68 mg, 0.075 mmol), and X-Phos (71 mg, 0.149 mmol) were added in a 150 mL RBF under Ar atmosphere. A degassed solution of THF (40 mL) and 2 M K3PO4 (5.0 mL) were injected to the reaction solution. The mixture was heated at 75 °C overnight. After cooling to RT, the resulting mixture was diluted with CH2Cl2 (200 mL) and washed with H2O (2 × 200 mL). The CH2Cl2 layer was collected and concentrated via rotary evaporator.
The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 5c (1.6 g, 2.436 mmol, 98%) as dark purple powder. 1H NMR (400 MHz, chloroform-d1):
10.01 (s, 1H), 8.99 (d, J = 3.6 Hz, 1H), 8.91 (dd, J = 3.6, 0.8 Hz, 1H), 7.65 (bs, 1H), 7.64 (dd, J = 5.2, 0.8 Hz, 2H), 7.28 (dd, J = 5.2, 4.0 Hz, 1H), 7.04 (d, J = 3.6 Hz, 1H), 4.03 (m, 4H), 2.28 (s, 6H), 1.98–
1.88 (m, 2H), 1.37–1.25 (m, 16H), 0.91–0.81 (m, 12H). 13C NMR (100 MHz, chloroform-d1): 192.15, 161.76, 161.67, 154.44, 140.47, 139.96, 139.33, 138.96, 136.26, 135.90, 135.35, 130.63, 130.59, 129.79, 128.62, 128.44, 128.25, 108.03, 107.95, 45.92, 45.89, 39.21, 39.05, 30.18, 30.12, 30.09, 28.35, 28.33, 23.52, 23.40, 23.04, 22.99, 20.86, 14.00, 13.96, 10.47, 10.39. FTIR (neat, cm−1): 3080, 2955, 2925, 2870, 2856, 2720, 1698, 1660, 1557, 1452, 1399, 1379, 1313, 1288, 1228, 1141, 1098, 1066, 1025, 974, 926, 857, 736, 716. HRMS (LC/Q-TOF) calc. for C39H49N2O3S2 = 657.3179. Found: m/z = 657.3192 [(M+H)+]. Mass error = 1.98 ppm.
4-(5-(4-(5-bromothiophen-2-yl)-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4- c]pyrrolyl)thiophen-2-yl)benzaldehyde (6a).1 To a suspension of compound 5a (400 g, 0.636 mmol) in CHCl3 (30 mL) at 25 °C was added NBS (125 mg, 0.700 mmol) under Ar atmosphere. The mixture was stirred at 25 °C for 300 min under absence of light. The resulting solution was diluted with CHCl3 (200 mL) and washed with H2O (2 × 200 mL). The CHCl3 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to
afford compound 6a (380 mg, 0.537 mmol, 84%) as purple powder. 1H NMR (400 MHz, chloroform- d1): 10.04 (s, 1H), 8.94 (d, J = 4.0 Hz, 1H), 8.68 (d, J = 4.0, 1H), 7.94 (dd, J = 6.8, 2.0 Hz, 2H), 7.83 (dd, J = 6.4, 1.2 Hz, 2H), 7.60 (d, J = 4.4 Hz, 1H), 7.24 (d, J = 4.4 Hz, 1H), 4.08–3.95 (m, 4H), 1.90 (m, 2H), 1.38–1.25 (m, 16H), 0.93–0.85 (m, 12H).
4-(5-(4-(5-bromothiophen-2-yl)-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4- c]pyrrolyl)thiophen-2-yl)-3-methylbenzaldehyde (6b). To a suspension of compound 5b (417 g, 0.649 mmol) in CHCl3 (30 mL) at 25 °C was added NBS (127 mg, 0.713 mmol) under Ar atmosphere. The reaction solution was stirred at 25 °C for 300 min under absence of light. The resulting solution was diluted with CHCl3 (200 mL) and washed with H2O (2 × 200 mL). The CHCl3 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 6b (350 mg, 0.485 mmol, 75%) as purple powder. 1H NMR (400 MHz, chloroform-d1): 10.02 (s, 1H), 8.95 (d, J = 4.0 Hz, 1H), 8.65 (d, J = 4.0 Hz, 1H), 7.81 (s, 1H), 7.76 (dd, J = 8.0, 1.2 Hz, 1H), 7.64 (d, J = 8.0 Hz, 1H), 7.34 (d, J = 4.0 Hz, 1H), 7.22 (d, J = 4.0 Hz, 1H), 4.04–3.93 (m, 4H), 2.59 (s, 3H), 1.90 (m, 2H), 1.37–1.25 (m, 16H), 0.91–0.85 (m, 12H). 13C NMR (100 MHz, chloroform-d1): 191.64, 161.52, 161.44, 147.05, 140.15, 138.64, 136.88, 135.97, 135.31, 132.36, 131.41, 131.15, 130.73, 130.46, 128.87, 127.46, 118.90, 108.21, 108.17, 45.98, 39.25, 39.07, 30.21, 30.13, 28.45, 28.28, 23.53, 23.05, 23.00, 21.46, 14.01, 14.00, 10.46. FTIR (neat, cm−1):
3087, 2957, 2927, 2872, 2857, 2722, 1697, 1663, 1601, 1554, 1452, 1413, 1399, 1379, 1294, 1234, 1162, 1101, 1073, 1028, 971, 814, 776, 733, 711. HRMS (LC/Q-TOF) calc. for C38H46BrN2O3S2 = 721.2128. Found: m/z = 721.2126 [(M+H)+]. Mass error = −0.14 ppm.
4-(5-(4-(5-bromothiophen-2-yl)-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4- c]pyrrolyl)thiophen-2-yl)-3,5-dimethylbenzaldehyde (6c). To a suspension of compound 5c (1.06 g, 1.614 mmol) in CHCl3 (30 mL) at 25 °C was added NBS (316 mg, 1.775 mmol) under Ar atmosphere.
The reaction solution was stirred at 25 °C for 300 min under absence of light. The resulting solution was diluted with CHCl3 (300 mL) and washed with H2O (2 × 300 mL). The CHCl3 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 6c (880 mg, 1.196 mmol, 74%) as purple powder. 1H NMR (400 MHz, chloroform-d1): 10.01 (s, 1H), 9.00 (d, J = 4.0 Hz, 1H), 8.65 (d, J = 4.4 Hz, 1H), 7.65 (s, 2H), 7.24 (d, J = 4.0 Hz, 1H), 7.04 (d, J = 4.0 Hz, 1H), 4.01–3.94 (m, 4H), 2.27 (s, 6H), 1.88–1.85 (m, 2H), 1.37–1.22 (m, 16H), 0.92–0.81 (m, 12H). 13C NMR (100 MHz, chloroform-d1): 192.15, 161.61, 161.53, 145.82, 140.44, 139.32, 139.01, 138.89, 136.31, 136.20, 135.20, 131.43, 131.22, 130.51, 128.64, 128.35, 118.77, 108.20, 107.92, 46.00, 39.21, 39.11, 30.17, 30.12, 29.69, 29.10, 28.35, 28.32, 23.56, 23.40, 23.03, 23.01, 20.86, 14.02, 13.98, 10.48, 10.39. FTIR (neat, cm−1): 3081, 2957, 2925, 2871, 2856, 2721, 1698, 1664, 1603, 1563, 1507, 1455, 1413, 1398, 1378, 1292, 1259, 1228, 1142, 1099, 1074, 1027, 973, 927, 872, 804, 735, 718. HRMS (LC/Q-TOF) calc. for C H BrNOS = 735.2284. Found:
m/z = 735.2292 [(M+H)+]. Mass error = 0.95 ppm.
4-(5-(4-(5-(4-(4-(2,2-diphenylvinyl)phenyl)-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indol-7- yl)thiophen-2-yl)-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrolyl)thiophen-2- yl)benzaldehyde (7a). Compound 6a (200 mg, 0.283 mmol), compound D1 (258 mg, 0.565 mmol), Pd2(dba)3 (13 mg, 0.014 mmol) X-Phos (13 mg, 0.028 mmol), and K3PO4 (180 mg, 0.848 mmol) were added in a 100 mL RBF under Ar atmosphere. A degassed solution of toluene (18 mL), tert-amyl alcohol (3.0 mL), and H2O (2.0 mL) was injected to the reaction solution. The mixture was heated at 70 °C overnight. After cooling to RT, the resulting mixture was diluted with CHCl3 (200 mL) and washed with H2O (2 × 200 mL). The CHCl3 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 7a (260 mg, 0.250 mmol, 88%) as dark purple solid after trituration with CH2Cl2 and MeOH. 1H NMR (400 MHz, chloroform-d1): 10.00 (s, 1H), 9.07 (dt, J = 4.4, 1.2 Hz, 1H), 8.88 (d, J = 4.0 Hz, 1H), 7.91 (d, J = 8.4 Hz, 2H), 7.80 (d, J = 3.2 Hz, 2H), 7.56 (d, J = 4.0 Hz, 1H), 7.42–7.34 (m, 5H), 7.34–7.26 (m, 8H), 7.03 (q, J = 8.0 Hz, 4H), 6.96 (d, J = 8.4 Hz, 1H), 6.94 (s, 1H), 4.76 (m, 1H), 4.07 (m, 4H), 3.82 (m, 1H), 2.12–2.03 (m, 2H), 1.92–1.65 (m, 6H), 1.42–1.26 (m, 16H), 0.94–0.86 (m, 12H). 13C NMR (100 MHz, chloroform-d1): 191.18, 161.93, 161.31, 152.10, 147.83, 146.30, 143.47, 141.27, 140.89, 140.69, 140.65, 138.81, 138.22, 137.50, 136.28, 135.74, 135.69, 131.02, 130.50, 130.45, 130.33, 128.78, 128.17, 127.48, 127.35, 127.26, 126.14, 126.06, 125.94, 123.87, 122.46, 122.39, 118.46, 118.44, 109.12, 108.50, 107.28, 68.91, 45.95, 45.08, 39.30, 39.18, 34.88, 33.73, 30.90, 30.36, 28.60, 24.35, 23.69, 23.13, 23.09, 14.08, 10.60, 10.54. FT-IR (neat, cm−1): 3078, 3055, 3026, 2955, 2928, 2869, 2858, 2732, 1698, 1662, 1597, 1553, 1509, 1486, 1444, 1421, 1400, 1379, 1327, 1307, 1264, 1233, 1214, 1168, 1104, 1083, 1027, 833, 809, 761, 734, 699. HRMS (LC/Q-TOF) calc. for C68H70N3O3S2 = 1040.4853. Found: m/z = 1040.4850 [(M+H)+]. Mass error = −0.29 ppm.
4-(5-(4-(5-(4-(4-(2,2-diphenylvinyl)phenyl)-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indol-7- yl)thiophen-2-yl)-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrolyl)thiophen-2- yl)-3-methylbenzaldehyde (7b). Compound 6b (350 mg, 0.485 mmol), compound D1 (444 mg, 0.970 mmol), Pd2(dba)3 (22 mg, 0.024 mmol), X-Phos (23 mg, 0.048 mmol), and K3PO4 (308 mg, 1.455 mmol) were added in a 100 mL RBF under Ar atmosphere. A degassed solution of toluene (24 mL) with Ar- gas, tert-amyl alcohol (4.0 mL), and H2O (3.0 mL) was injected to the mixture. The resulting mixture was heated at 70 °C overnight. After cooling to RT, the resulting mixture was diluted with CHCl3 (200 mL) and washed with H2O (2 × 200 mL). The CHCl3 layer was collected and concentrated via rotary evaporator. The remaining mixture was purified by chromatography using a single solvent (CHCl3) to afford compound 7b (500 mg, 0.474 mmol, 98%) as dark purple solid after trituration with CH2Cl2 and MeOH. 1H NMR (400 MHz, chloroform-d1): 10.03 (s, 1H), 9.06 (dt, J = 4.4, 1.2 Hz, 1H), 8.90 (d, J = 4.0 Hz, 1H), 7.82 (s, 1H), 7.77 (dd, J = 8.0, 1.2 Hz, 1H), 7.65 (d, J = 8.0 Hz, 1H), 7.41–7.37 (m, 5H),