## 3 Materials and Methods
#### Synthesis of the Starting Substrates
\({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 8.49-8.47 (m, 1H), 8.37 (s, 1H), 7.66-7.64 (m, 1H), 7.62-7.58 (m, 2H), 7.32-7.26 (m, 2H), 7.25-7.20 (m, 2H), 4.92-4.82 (m, 1H), and 1.55 (d, \(J\) = 6.8 Hz, 6H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 148.5, 137.5 (br.s), 135.9, 126.4, 125.2, 122.3, 121.9, 121.2, 120.8, 113.8 (br.s), 110.5, 104.5, 47.1, and 22.3 ppm. HRMS (ESI) calcd for C\({}_{18}\)H\({}_{18}\)N\({}_{3}\) [M+H]\({}^{+}\) 276.1495; found 276.1496. _2-(1-Phenyl-1H-indol-3-yl)-1H-benzo[d]imidazole_ isolated as a solvate with DMAC (1:0.SDMAC) (**3e**). A yield of 0.418 g (84%), 7 h, light-beige solid. Mp. = 231-232 \({}^{\circ}\)C (EtOH). \({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 8.68-8.64 (m, 1H), 8.44 (br.s, 1H), 7.72-7.59 (m, 7H), 7.53-7.48 (m, 1H), 7.37-7.32 (m, 2H), and 7.22-7.17 (m, 2H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 148.2, 138.3, 135.8, 130.0, 128.7, 127.2, 126.2, 124.0, 123.4, 122.0, 121.5, 114.2 (br.s), 110.7, and 108.1 ppm. HRMS (ESI) calcd for C\({}_{21}\)H\({}_{16}\)N\({}_{3}\) [M+H]\({}^{+}\) 310.1339; found 310.1346. _2-(1-Benzyl-1H-indol-3-yl)-1H-benzo[d]imidazole_ (**3f**) [59]. A yield of 0.399 g (95%), 6.5 h, light-beige solid. Mp. = 214-215 \({}^{\circ}\)C (DMAC/H\({}_{2}\)O, lit. [59] 218-220 \({}^{\circ}\)C). \({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 8.52-8.49 (m, 1H), 8.28 (s, 1H), 7.64-7.57 (m, 3H), 7.38-7.24 (m, 7H), 7.22-7.18 (m, 2H), and 5.56 (s, 2H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 148.4, 137.9 (br.s), 137.3, 136.5, 129.9, 128.6, 127.6, 127.3, 125.4, 122.6, 121.7, 121.3, 120.8, 113.9 (br.s), 110.7, 105.3, and 49.5 ppm. _2-(1-Butyl-1H-indol-3-yl)-1H-benzo[d]imidazole_ (**3g**) [58]. A yield of 0.368 g (98%), 6 h, light-beige solid. Mp. = 190-192 \({}^{\circ}\)C, decomposition (DMAC/H\({}_{2}\)O, lit. [58] 207-208 \({}^{\circ}\)C). \({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 8.47 (d, \(J\) = 7.6 Hz, 1H), 8.25 (s, 1H), 7.63-7.59 (m, 3H), 7.32-7.21 (m, 4H), 4.30 (t, \(J\) = 6.8 Hz, 2H), 1.87-1.79 (m, 2H), 1.38-1.28 (m, 2H), and 0.93 (t, \(J\) = 7.2 Hz, 3H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 147.3, 136.3 (br.s), 135.4, 129.1, 124.1, 121.0, 120.1, 119.7, 112.8, 109.5, 103.0, 44.6, 30.5, 18.3, and 12.4 ppm. _2-(2-Phenyl-1H-indol-3-yl)-1H-benzo[d]imidazole_ isolated as a solvate with DMAC (1:0.3 DMAC) (**3h**), for no solvate [60]. A yield of 0.421 g (96%), 7 h, brown solid. Mp. = 132-133 \({}^{\circ}\)C (EtOH, lit. for not solvate [60] 357-358 \({}^{\circ}\)C). \({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 11.96 (br.s, 1H), 7.85 (d, \(J\) = 8.0 Hz, 1H), 7.67-7.64 (m, 2H), 7.60-7.55 (m, 2H), 7.52 (d, \(J\) = 8.0 Hz, 1H), 7.48-7.39 (m, 3H), 7.27-7.21 (m, 3H), and 7.19-7.15 (m, 1H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 144.1, 134.6,_2-{2-(4-Fluorophenyl)-1H-indol-3-yl}-1H-benzo[d]imidazole_ (**3j**). A yield of 0.332 g (78%), 6 h, light-beige solid. Mp. = 283-284 \({}^{\circ}\)C (DMAC/H\({}_{2}\)O). \({}^{1}\)H NMR (400 MHz, DMSO-\(d_{6}\)) \(\delta\) = 12.03 (brs, 1H), 11.84 (s, 1H), 7.89 (d, \(J\) = 8.0 Hz, 1H), 7.75-7.70 (m, 2H), 7.54-7.43 (m, 3H), 7.33-7.27 (m, 2H), 7.25-7.21 (m, 1H), and 7.18-7.13 (m, 3H) ppm; \({}^{13}\)C[\({}^{1}\)H] NMR (100 MHz, DMSO-\(d_{6}\)) \(\delta\) = 162.0 (d, \(J_{\rm CF}\) = 244.0 Hz), 148.0, 136.5, 135.9, 130.5 (d, \(J_{\rm CF}\) = 8.0 Hz), 128.2 (d, \(J_{\rm CF}\) = 3.0 Hz), 127.8, 122.4, 121.2, 121.1, 120.2, 120.0, 115.4 (d, \(J_{\rm CF}\) = 22.0 Hz), 111.4, and 103.6 ppm. HRMS (ESI) calcd for C\({}_{21}\)H\({}_{15}\)FN\({}_{3}\) [M+H]\({}^{+}\) 328.1245; found 328.1253. _2-{(Thiophen-2-yl)-1H-indol-3-yl}-1H-benzo[d]imidazole_ (**3k**) [60]. A yield of 0.229 g (56%), 6 h, yellow needles. Mp. = 241-242 \({}^{\circ}\)C, decomposition (EtOH, lit. [61] 201-203 \({}^{\circ}\)C).