Effect of Conjugation and Aromaticity of 3,6 Di-substituted Carbazole On Triplet Energy

Transcription

1 Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 2018 Electronic Supporting Information (ESI) for Effect of Conjugation and Aromaticity of 3,6 Di-substituted Carbazole On Triplet Energy Kai Lin Woon a*, Azhar Ariffin b**, Kar Wei Ho b, Show-An Chen c a Low Dimensional Materials Research Center, Department of Physics, University of Malaya, Malaysia b Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia c Department of Chemical Engineering and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing-Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu, Taiwan, ROC Contents I General methods 1 II Synthesis procedures 2 III Copies of 1H, 13C NMR and mass spectrum for synthesized compounds 13 IV Torsional Angle.. 32 V Coordinates of Stationary Points in xyz format 33

2 I. General methods Proton and carbon nuclear magnetic resonance spectroscopy ( 1 H NMR and 13 C NMR spectra) were obtained on a Bruker AVANCE III 400 MHz FT-NMR spectrometer using deuterated chloroformas the solvent with tetramethylsilane (TMS) as internal standard. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) measurements were carried out with a Bruker Microflex series spectrometer in order to measure the molecular masses. 2,5-dihydroxybenzoic acid (DHB) was used as matrix. 2

3 II. Synthesis procedures Bis(4-bromophenyl)diphenylsilane, (1), Known compound. Br Si Br Compound 1 was prepared according to modified procedure from the literature. 20 1,4- Dibromobenzene (4.20 g, 17.8 mmol) was dissolved in 15mL dry THF under nitrogen atmosphere. The solution was cooled to -78 C. 9.6 ml of n-buli (2.0 M in cyclohexane) was added dropwise and stir for 1 h. Dichlorodiphenylsilane (1.68 ml, 8 mmol) was added slowly at -78 C. The mixture was stirred overnight while allowing the temperature to rise to room temperature. The reaction was then quenched with water and extracted with chloroform. The organic layer was dried over anhydrous sodium sulfate. After the solvent was evaporated, the crude product was purified by recrystallization from ethanol to afford white solid (2.54 g, 64.3 %). Melting point = C. 1 HNMR (CDCl 3, 400 MHz): δ (ppm) = (m, 8H), (m, 10H). 13 C NMR (CDCl 3, 100 MHz): δ (ppm) = , , , , , , , ,6-Diiodocarbazole, (2), Known compound. I I N H Carbazole (8.36 g, 50 mmol) was dissolved in boiling acetic acid (200 ml). To the solution, potassium iodide (10.8 g, 50 mmol) was added. The solution was cooled and potassium iodate (21.5 g, 50 mmol) was added. Solution was refluxed at 80 ºC for 1 h. The solution was decanted from undissolved potassium iodate and it was allowed to cool to room temperature. The crude product obtained was filtered and recrystallized from dichloromethane to give brown solid (13.97 g, 66.7%). Melting point = C. 1 H NMR (CDCl 3, 400 MHz): δ (ppm) = 8.36 (s, 2H), 8.14 (br, s, 1H), 7.71 (dd, 2H, J=8.50, 1.65 Hz), 7.24 (d, 2H, J=8.56 Hz). 13 C NMR (CDCl 3, 100 MHz): δ (ppm) = , , , , ,

4 3,6-bis(4-(tert-butyl)phenyl)-9H-carbazole, (3), Known compound. N H Compound 3 was prepared using Suzuki coupling reaction. 4-Tert-butylphenylboronic acid (1.1 g, 6.2 mmol) and compound 4 (1.25 g, 3 mmol) were dissolved in 25 ml toluene in a round bottom flask under nitrogen. A solution of potassium carbonate (2M, 1.7 ml) was added to the solution. tetrakis(triphenylphosphine)palladium(0) (0.14 g, 0.12 mmol) was added. The reaction mixture was reflux for 24 h under nitrogen. After cooling to room temperature, the reaction mixture was evaporated to remove solvent and extracted with chloroform and water. The organic layer was removed under reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid (yield 85.6%, 1.11 g). Melting point, decompose > 200 C 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.34 (d, J=1.71 Hz, 2H), 8.13 (s, 1H), (m, 6H), (m, 6H), 1.42 (s, 18H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , 34.51, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 32 H 33 N ; Found ,6-bis(3-methoxyphenyl)-9H-carbazole (4), known compound. O O N H Compound 4 was prepared using Suzuki coupling reaction. 3-Methoxyphenylboronic acid (3.17 g, 20.9 mmol) and compound 2 (3.98 g, 9.49 mmol) were dissolved in 40 ml toluene in a round bottom flask under nitrogen. A solution of potassium carbonate (2M, 10 ml) was added to the solution. tetrakis(triphenyl-phosphine)palladium(0) (0.47 g, 0.41 mmol) was added. The reaction mixture was reflux for 24 h under nitrogen. After cooling to room temperature, the reaction mixture was evaporated to remove solvent and extracted with chloroform and water. The organic layer was removed under 4

5 reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid 6 (yield 17.4%, 0.63 g). Melting point, decompose > 200 C. 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.36 (d, J=1.83 Hz, 2H), 8.17 (s, 1H), 7.72 (dd, J=8.24, 1.83 Hz, 2H), 7.53, (d, J=8.24 Hz, 2H), (m, 2H), (m, 2H), (m, 2H), (m, 2H), 3.94 (s, 6H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 26 H 21 NO ; Found ,6-bis(4-fluorophenyl)-9H-carbazole, (5), known compound. F F N H Compound 5 was prepared using Suzuki coupling reaction. 4-fluorophenylboronic acid (0.93 g, 6.7 mmol) and compound 2 (1.27 g, 3.03 mmol) were dissolved in 24 ml toluene in a round bottom flask under nitrogen. A solution of potassium carbonate (2M, 6 ml) was added to the solution. tetrakis(triphenyl-phosphine)palladium(0) (0.13 g, 0.11 mmol) was added. The reaction mixture was reflux for 24 h under nitrogen. After cooling to room temperature, the reaction mixture was evaporated to remove solvent and extracted with chloroform and water. The organic layer was removed under reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid 7 (yield 30.4%, 0.33 g). Melting point, decompose > 200 C. 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.29 (s, 2H), 8.17 (br. s., 1H), (m, 6H), 7.53 (d, J=8.44 Hz, 2H), 7.19 (t, J=8.68 Hz, 4H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 24 H 15 F 2 N ; Found ,6-bis(4-methoxyphenyl)-9H-carbazole, (6), known compound. MeO OMe N H Compound 6 was prepared using Suzuki coupling reaction. 4-methoxyphenylboronic acid (1.31 g, 8.6 mmol) and compound 2 (1.51 g, 3.6 mmol) were dissolved in 30 ml toluene in a round bottom flask 5

6 under nitrogen. A solution of potassium carbonate (2M, 3.6 ml) was added to the solution. tetrakis(triphenyl-phosphine)palladium(0) (0.17 g, 0.14 mmol) was added. The reaction mixture was reflux for 24 h under nitrogen. After cooling to room temperature, the reaction mixture was evaporated to remove solvent and extracted with chloroform and water. The organic layer was removed under reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid 8 (yield 43.5%, 1.13 g). Melting point = C 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: 8.30 (s, 2H), 8.10 (br. s., 1H), (m, 6H), 7.50 (d, J=8.25 Hz, 2H), (m, 4H), 3.90 (s, 6H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 26 H 21 NO ; Found ,6-diiodo-9-tosyl-9H-carbazole, (8), known compound. O S O N I I Compound 8 was prepared according to procedure from the literature. 2 To a solution of compound 2 (2.01 g, 4.8 mmol) in N,N-dimethylformamide (20 ml) was added sodium hydride (0.84 g, 35 mmol) at 0 ºC, and stirred for 10 mins. Subsequently, p-toluenesulfonyl chloride (2.9 g, 15.8 mmol) was added to this mixture and stirred at 0ºC for 4 h. the mixture was diluted with water and the precipitates were filtered. The crude product was recrystallized from dichloromethane to afford compound 8 (3.0 g, 62.4 %) as white solid. Melting point, decompose > 250 C 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.20 (d, J=1.59 Hz, 2H), 8.10 (d, J=8.80 Hz, 2H), 7.80 (dd, J=8.74 Hz, 2H), 7.67 (d, J=8.44 Hz, 2H), 7.16 (d, J=8.07 Hz, 2H), 2.32 (s, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , 87.96, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 19 H 13 I 2 NO 2 S ; Found ,6-di-tert-butyl-9H-carbazole, (7), known compound. N H 6

7 In ice bath of 0 ºC, carbazole (20 mmol) was suspended in 100 ml chloroform under nitrogen. AlCl 3 (2.67 g, 20 mmol) was added in portions. Tert-butyl chloride (5.3 ml, 24 mmol) was then added drop wise. Then the mixture was stirred for 12 h. The reaction was quenched by ice water, and extracted by chloroform. The organic layer was dried with anhydrous Na 2 SO 4 and the solvent was removed under reduced pressure to obtain white solid. Yield: 82.6%. Melting point = C. 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.10 (s, 2H), 7.88 (br. s., 1H), 7.49 (d, J=8.44 Hz, 2H), 7.36 (d, J=8.44 Hz, 2H), 1.48 (s, 18 H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , 34.69, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 20 H 25 N ; Found ,3'',6,6''-tetrakis(4-methoxyphenyl)-9'-tosyl-9'H-9,3':6',9''-tercarbazole (9), New compound. O S N O O N N O O O Compound 9 was prepared according to procedure from the literature. 1 A solution of compound 8 (1.16 g, 2.03 mmol) and compound 6 (1.68 g, 4.42 mmol) in N,N-dimethylacetamide (10 ml) was prepared. Copper oxide (0.59 g, 4.1 mmol) was added to the solution. The mixture was then refluxed for 48 h and cooled to room temperature. After cooling to room temperature, the reaction mixture was evaporated under reduced pressure to remove solvent and extracted with chloroform and water. The organic layer was evaporated under reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid with (yield 49.1 %, 1.07 g). Melting point, decompose > 300 C. 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.66 (d, J=8.80 Hz, 2H), 8.36 (d, J=1.35 Hz, 4H), 8.18 (d, J=1.83 Hz, 2H), 7.98 (d, J=8.44 Hz, 2H), 7.83 (dd, J=8.93, 2.08 Hz, 2H), 7.66 (d, J=8.80 Hz, 8H), 7.63 (dd, J=8.25, 1.83 Hz, 4H), 7.46 (d, J=8.56 Hz, 4H), 7.35 (d, J=8.07 Hz, 2H), 7.04 (d, J=8.80 Hz, 8H), 3.90 (s, 12H), 2.44 (s, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , , , 55.41, HRMS (MALDI-TOF) m/z: [M]+ Calcd for 7

8 C 71 H 53 N 3 O 6 S ; Found ,3'',6,6''-tetra-tert-butyl-9'-tosyl-9'H-9,3':6',9''-tercarbazole (10), Known compound. O S N O N N Compound 10 was prepared according to procedure from the literature. 1 A solution of compound 8 (1.44 g, 2.51 mmol) and compound 7 (1.54 g, 5.5 mmol) in N,N-dimethylacetamide (10 ml) was prepared. Copper oxide (0.73 g, 5.1 mmol) was added to the solution. The mixture was then refluxed for 48 h and cooled to room temperature. After cooling to room temperature, the reaction mixture was evaporated under reduced pressure to remove solvent and extracted with chloroform and water. The organic layer was evaporated under reduced pressure, and the residue was subjected to a column chromatography using hexane/ethyl acetate as the eluent to obtain white solid with yield of 65.5% (1.44 g). Melting point = decompose > 300 C. 1 H NMR (600M Hz, CDCl 3 ) δ [ppm]: 8.59 (d, J=8.80 Hz, 2H), 8.16 (d, J=1.65 Hz, 4H), 8.07 (d, J=2.02 Hz, 2H), 7.94 (d, J=8.25 Hz, 2H), 7.75 (dd, J=8.80, 2.20 Hz, 2H), 7.47 (dd, J=8.62, 2.02 Hz, 4H), 7.35 (d, J=8.25 Hz, 4H), 7.32 (d, J=8.25 Hz, 2H), 2.42 (s, 3H), 1.48 (s, 36H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , 34.74, 32.00, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 59 H 61 N 3 O 2 S ; Found ,3'',6,6''-tetrakis(4-methoxyphenyl)-9'H-9,3':6',9''-tercarbazole (11), New compound. H N O N N O O O Compound 11 was prepared according to the procedure from the literature. 1 To a solution of compound 9 (1.04 g, mmol) in 9 ml tetrahydrofuran were added dimethyl sulfoxide (2.45 ml) and water (1.0 8

9 ml), and the mixture was stirred for 10 mins. Subsequently, potassium hydroxide (1.36 g, mol) was added to this mixture, and the reaction mixture was refluxed for 4 hours, cooled to room temperature and diluted with water. After neutralization with HCl solution, the crude product was filtered and recrystallized from dichloromethane-hexane (1:1) to give compound 11 as white solid (yield 99.4 %, g). Melting point, decompose > 300 C, 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: 8.62 (br. s., 1H), (m, 6H), (m, 20H), 7.04 (d, J=8.80 Hz, 8H), 3.89 (s, 12H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 64 H 47 N 3 O ; Found ,3'',6,6''-tetra-tert-butyl-9'H-9,3':6',9''-tercarbazole (12), Known compound. H N N N Compound 12 was prepared according to the procedure from the literature. 1 To a solution of compound 10 (1.39 g, 1.59 mmol) in 10 ml tetrahydrofuran were added dimethyl sulfoxide (4.8 ml) and water (1.6 ml), and the mixture was stirred for 10 mins. Subsequently, potassium hydroxide (1.59 g, 0.03 mol) was added to this mixture, and the reaction mixture was refluxed for 4 hours, cooled to room temperature and diluted with water. After neutralization with HCl solution, the crude product was filtered and recrystallized from dichloromethane-hexane (1:1) to give compound 12 as white solid (yield 99.5%, 1.14 g). Melting point, decompose > 300 C. 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: 8.52 (br. s., 1H), 8.18 (d, J=1.65 Hz, 6H), 7.70 (d, J=8.16 Hz, 2H), 7.63 (dd, J=8.48, 1.88 Hz, 2H), 7.47 (dd, J=8.57, 1.65 Hz, 4H), 7.33 (d, J=8.07 Hz, 4H), 1.48 (s, 36H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , 34.73, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 52 H 55 N ; Found Bis(4-(3,6-bis(4-(tert-butyl)phenyl)-9H-carbazol-9-yl)phenyl)diphenylsilane, P1, New compound. 9

10 N Si N Compound 1 (0.25 g, 0.51 mmol), carbazole 3 (0.48 g, 1.12 mmol), copper powder (0.13 g, 2.05 mmol), and 18-Crown-6 (0.013 g, mmol) and K 2 CO 3 (0.55 g, 4.0 mmol) were dissolved in 4 ml anhydrous o-dichlorobenzene under nitrogen atmosphere. The reaction mixture was refluxed for 72 h at 180 ºC. After cooling to room temperature, the mixture was diluted in dichloromethane and filtered through silica gel. The filtrate was evaporated under reduced pressure to give crude product, which purified through column chromatography to give white powdery product (yield 20.1 %, 0.123g). Melting point, decompose > 300 C. 1 H NMR (400 MHz, CDCl 3 ) δ [ppm]: 8.41 (d, J=1.47 Hz, 4H), 7.95 (d, J=8.31 Hz, 4H), (m, 38H), 1.42 (s, 36H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , 34.52, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 88 H 82 N 2 Si ; Found Bis(4-(3,6-bis(3-methoxyphenyl)-9H-carbazol-9-yl)phenyl)diphenylsilane, P2. New compound. O O N Si N O O Compound 1 (0.20 g, mmol), carbazole 4 (0.33 g, 0.86 mmol), copper powder (0.10 g, 1.57 mmol), and 18-Crown-6 (0.011 g, mmol) and K 2 CO 3 (0.44 g, 3.2 mmol) were dissolved in 4 ml anhydrous o-dichlorobenzene under nitrogen atmosphere. The reaction mixture was refluxed for 72 h at 180 ºC. After cooling to room temperature, the mixture was diluted in dichloromethane and filtered through silica gel. The filtrate was evaporated under reduced pressure to give crude product, which purified through column chromatography to give white powdery product (yield 27.7%, g). Melting point, 10

11 decompose > 300 C. 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: 8.43 (d, J=1.47 Hz, 4H), 7.96 (d, J=8.25 Hz, 4H), 7.79 (dd, J=7.98, 1.56 Hz, 4H), 7.75 (d, J=8.25 Hz, 4H), 7.72 (dd, J=8.53, 1.47 Hz, 4H), 7.64 (d, J=8.44, 4H), (m, 6H), (m, 4H), 7.35 (d, J=8.07 Hz, 4H), (m, 4H), 6.94 (dd, J=8.25, 1.83 Hz, 4H), 3.94 (s, 12H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 76 H 58 N 2 O 4 Si ; Found Bis(4-(3,6-bis(4-fluorophenyl)-9H-carbazol-9-yl)phenyl), P3. New compound. F F N Si N F F Compound 1 (0.20 g, 0.40 mmol), carbazole 5 (0.31 g, 0.87 mmol), copper powder (0.10 g, 1.57 mmol), and 18-Crown-6 (0.011 g, mmol) and K 2 CO 3 (0.44 g, 3.2 mmol) were dissolved in 4 ml anhydrous o-dichlorobenzene under nitrogen atmosphere. The reaction mixture was refluxed for 72 h at 180 ºC. After cooling to room temperature, the mixture was diluted in dichloromethane and filtered through silica gel. The filtrate was evaporated under reduced pressure to give crude product, which purified through column chromatography to give white powdery product (yield 16.9%, g). Melting point, decompose > 300 C. 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: (m, 4H), 7.97 (d, J=8.25 Hz, 2H), (m, 32H), (m, 8H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 72 H 46 F 4 N 2 Si ; Found Diphenylbis(4-(3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'H-[9,3':6',9''-tercarbazol]-9'- yl)phenyl)silane, P4. New compound. 11

12 O O O N N O N Si N O N N O O O Compound 1 (0.22 g, 0.45 mmol), carbazole 11 (0.89 g, 0.97 mmol), copper powder (0.11 g, 1.73 mmol), and 18-Crown-6 (0.012 g, mmol) and K 2 CO 3 (0.49 g, 3.5 mmol) were dissolved in 4 ml anhydrous o-dichlorobenzene under nitrogen atmosphere. The reaction mixture was refluxed for 72 h at 180 ºC. After cooling to room temperature, the mixture was diluted in dichloromethane and filtered through silica gel. The filtrate was evaporated under reduced pressure to give crude product, which purified through column chromatography to give white powdery product (yield 43.3%, 0.41 g). Melting point, decompose > 300 C. 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: (m, 12H), (m, 44H), (m, 14H), 7.04 (d, J=8.62 Hz, 16H), 3.90 (s, 24H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , , , , , , HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 152 H 110 N 6 O 8 Si ; Found Diphenylbis(4-(3,3'',6,6''-tetra-tert-butyl-9'H-[9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane, P5. New compound. N N N Si N N N 12

13 Compound 1 (0.28 g, 0.57 mmol), carbazole 10 (0.87 g, 1.20 mmol), copper powder (0.14 g, 2.20 mmol), and 18-Crown-6 (0.015 g, mmol) and K 2 CO 3 (0.61 g, 4.4 mmol) were dissolved in 4.5 ml anhydrous o-dichlorobenzene under nitrogen atmosphere. The reaction mixture was refluxed for 72 h at 180 ºC. After cooling to room temperature, the mixture was diluted in dichloromethane and filtered through silica gel. The filtrate was evaporated under reduced pressure to give crude product, which purified through column chromatography to give white powdery product (yield 17.9%, g). Melting point, decompose > 300 C. 1 H NMR (600 MHz, CDCl 3 ) δ [ppm]: 8.27 (d, J=1.83 Hz, 4H), 8.18 (d, J=1.65 Hz, 8H), 8.06 (d, J=8.25 Hz, 4H), 7.88 (d, J=8.25 Hz, 4H), (m, 4H), 7.79 (d, J=8.80 Hz, 4H), 7.65 (dd, J=8.71, 1.93 Hz, 4H), (m, 2H), 7.58 (d, J=7.34 Hz, 4H), 7.48 (dd, J=8.62, 1.83 Hz, 8H), 7.36 (d, J=8.26 Hz, 8H), 1.48 (s, 24H). 13 C NMR (100 MHz, CDCl 3 ) δ [ppm]: , , , , , , , , , , , , , , , , , , , 34.73, HRMS (MALDI-TOF) m/z: [M]+ Calcd for C 128 H 126 N 6 Si ; Found

14 III. Copies of 1H and 13C NMR for synthesized compounds Fig. S1. 1 H NMR spectrum (400 MHz) for bis(4-bromophenyl)diphenylsilane (Compound 1) in CDCl 3. Fig. S2. 13 C NMR spectrum (100 MHz) for bis(4-bromophenyl)diphenylsilane (Compound 1) in CDCl 3. 14

15 Fig. S3. 1 H NMR spectrum (400 MHz) for 3,6-diiodocarbazole (Compound 2) in CDCl 3. Fig. S4. 13 C NMR spectrum (100 MHz) for 3,6-diiodocarbazole (Compound 2) in CDCl 3. 15

16 Figure S5. 1 H NMR spectrum (400 MHz) for 3,6-bis(4-(tert-butyl)phenyl)-9H-carbazole (Compound 3) in CDCl 3. Figure S6. 13 C NMR spectrum (100 MHz) for 3,6-bis(4-(tert-butyl)phenyl)-9H-carbazole (Compound 3) in CDCl 3. Figure S7. MALDI-TOF MS spectrum for 3,6-bis(4-(tert-butyl)phenyl)-9H-carbazole (Compound 3) in CDCl 3. 16

17 Figure S8. 1 H NMR spectrum (400 MHz) for 3,6-bis(3-methoxyphenyl)-9H-carbazole (Compound 4) in CDCl 3. Figure S9. 13 C NMR spectrum (100 MHz) for 3,6-bis(3-methoxyphenyl)-9H-carbazole (Compound 4) in CDCl 3. Figure S10. MALDI-TOF MS spectrum for 3,6-bis(3-methoxyphenyl)-9H-carbazole (Compound 4) in CDCl 3. 17

18 Figure S11. 1 H NMR spectrum (400 MHz) for 3,6-bis(4-fluorophenyl)-9H-carbazole (Compound 5) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,6-bis(4-fluorophenyl)-9H-carbazole (Compound 5) in CDCl 3. Figure S13. MALDI-TOF MS spectrum for 3,6-bis(4-fluorophenyl)-9H-carbazole (Compound 5) in CDCl 3 18

19 Figure S14. 1 H NMR spectrum (600 MHz) for 3,6-bis(4-methoxyphenyl)-9H-carbazole (Compound 6) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,6-bis(4-methoxyphenyl)-9H-carbazole (Compound 6) in CDCl 3. Figure S16. MALDI-TOF MS spectrum for 3,6-bis(4-methoxyphenyl)-9H-carbazole (Compound 6) in CDCl 3. 19

20 Figure S17. 1 H NMR spectrum (400 MHz) for 3,6-diiodo-9-tosyl-9H-carbazole (Compound 8) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,6-diiodo-9-tosyl-9H-carbazole (Compound 8) in CDCl 3. Figure S19. MALDI-TOF MS spectrum for 3,6-diiodo-9-tosyl-9H-carbazole (Compound 8) in CDCl 3. 20

21 Figure S20. 1 H NMR spectrum (400 MHz) for 3,6-di-tert-butyl-9H-carbazole (Compound 7) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,6-di-tert-butyl-9H-carbazole (Compound 7) in CDCl 3. Figure S22. MALDI-TOF MS spectrum for 3,6-di-tert-butyl-9H-carbazole (Compound 7) in CDCl 3. 21

22 Figure S23. 1 H NMR spectrum (400 MHz) for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'-tosyl-9'H- 9,3':6',9''-tercarbazole (Compound 9) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'-tosyl-9'H- 9,3':6',9''-tercarbazole (Compound 9) in CDCl 3. Figure S25. MALDI-TOF MS spectrum for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'-tosyl-9'H- 9,3':6',9''-tercarbazole (Compound 9) in CDCl 3. 22

23 Figure S26. 1 H NMR spectrum (600 MHz) for 3,3'',6,6''-tetra-tert-butyl-9'-tosyl-9'H-9,3':6',9''- tercarbazole (Compound 10) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,3'',6,6''-tetra-tert-butyl-9'-tosyl-9'H-9,3':6',9''- tercarbazole (Compound 10) in CDCl 3. Figure S28. MALDI-TOF MS spectrum for 3,3'',6,6''-tetra-tert-butyl-9'-tosyl-9'H-9,3':6',9''- tercarbazole (Compound 10) in CDCl 3 23

24 Figure S29. 1 H NMR spectrum (600 MHz) for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'H-9,3':6',9''- tercarbazole (Compound 11) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'H-9,3':6',9''- tercarbazole (Compound 11) in CDCl 3. Figure S31. MALDI-TOF MS spectrum for 3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'H-9,3':6',9''- tercarbazole (Compound 11) in CDCl 3. 24

25 Figure S32. 1 H NMR spectrum (600 MHz) for 3,3'',6,6''-tetra-tert-butyl-9'H-9,3':6',9''-tercarbazole (Compound 12) in CDCl 3. Figure S C NMR spectrum (100 MHz) for 3,3'',6,6''-tetra-tert-butyl-9'H-9,3':6',9''-tercarbazole (Compound 12) in CDCl 3. Figure S33. MALDI-TOF MS spectrum for 3,3'',6,6''-tetra-tert-butyl-9'H-9,3':6',9''-tercarbazole (Compound 12) in CDCl 3. 25

26 Figure S34. 1 H NMR spectrum (400 MHz) for bis(4-(3,6-bis(4-(tert-butyl)phenyl)-9h-carbazol-9- yl)phenyl)diphenylsilane/p1 in CDCl 3. Figure S C NMR spectrum (100 MHz) for bis(4-(3,6-bis(4-(tert-butyl)phenyl)-9h-carbazol-9- yl)phenyl)diphenylsilane/p1 in CDCl 3. 26

27 Figure S36. MALDI-TOF MS spectrum for bis(4-(3,6-bis(4-(tert-butyl)phenyl)-9h-carbazol-9- yl)phenyl)diphenylsilane/p1 in CDCl 3. Figure S37. 1 H NMR spectrum (600 MHz) for bis(4-(3,6-bis(3-methoxyphenyl)-9h-carbazol-9- yl)phenyl)diphenylsilane/p2 in CDCl 3. Figure S C NMR spectrum (100 MHz) for bis(4-(3,6-bis(3-methoxyphenyl)-9h-carbazol-9-27

28 yl)phenyl)diphenylsilane/p2 in CDCl 3. Figure S39. MALDI-TOF MS spectrum for bis(4-(3,6-bis(3-methoxyphenyl)-9h-carbazol-9- yl)phenyl)diphenylsilane/p2 in CDCl 3. Figure S40. 1 H NMR spectrum (600 MHz) for bis(4-(3,6-bis(4-fluorophenyl)-9h-carbazol-9- yl)phenyl)/p3 in CDCl 3. Figure S C NMR spectrum (100 MHz) for bis(4-(3,6-bis(4-fluorophenyl)-9h-carbazol-9- yl)phenyl)/p3 in CDCl 3. 28

29 Figure S42. MALDI-TOF MS spectrum for bis(4-(3,6-bis(4-fluorophenyl)-9h-carbazol-9- yl)phenyl)/p3 in CDCl 3. Figure S43. 1 H NMR spectrum (600 MHz) for diphenylbis(4-(3,3'',6,6''-tetrakis(4-methoxyphenyl)- 9'H-[9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane/P4 in CDCl 3. Figure S C NMR spectrum (100 MHz) for diphenylbis(4-(3,3'',6,6''-tetrakis(4-methoxyphenyl)- 9'H-[9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane/P4 in CDCl 3. 29

30 Figure S45. MALDI-TOF MS spectrum for diphenylbis(4-(3,3'',6,6''-tetrakis(4-methoxyphenyl)-9'h- [9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane/P4 in CDCl 3. Figure S46. 1 H NMR spectrum (600 MHz) for diphenylbis(4-(3,3'',6,6''-tetra-tert-butyl-9'h- [9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane/P5 in CDCl 3. Figure S C NMR spectrum (100 MHz) for diphenylbis(4-(3,3'',6,6''-tetra-tert-butyl-9'h- [9,3':6',9''-tercarbazol]-9'-yl)phenyl)silane/P5 in CDCl 3. 30

31 Figure S48. MALDI-TOF MS spectrum for diphenylbis(4-(3,3'',6,6''-tetra-tert-butyl-9'h-[9,3':6',9''- tercarbazol]-9'-yl)phenyl)silane/p5 in CDCl 3. Reference 1. El-Khouly, M. E.; Lee, S.-H.; Kay, K.-Y.; Fukuzumi, S. New Journal of Chemistry 2013, 37,

32 IV. Torsional angle Figure S49 : Torsional angle between the carbazole and moiety at the 3,6 positions of the carbazole. The data is subtracted with its minimum torsional energy for ease of comparison. 32

33 I. Coordinates of Stationary Points in xyz format CarbO 21 C C C C C C C C O C C C C H H H H H H H H

34 Carb2O 30 C C C C C C C C O C C C C C C O C C C C H H H H H H H H H H

35 Carb3O 39 C C C C C C C C O C C C C C C O C C C C C C O C C C C H H H H H H H H H

36 H H H Carb4O 48 C C C C C C C C O C C C C C C O C C C C C C O C C C C C C O C C C C

37 H H H H H H H H H H H H H H Carb5O 57 C C C C C C C C O C C C C C C O

38 C C C C C C O C C C C C C O C C C C C C O C C C C H H H H H H H H H H H H H H H H

39 Carb6O 66 C C C C C C C C O C C C C C C O C C C C C C O C C C C C C O C

40 C C C C C O C C C C C C O C C C C H H H H H H H H H H H H H H H H H H

41 CarbN 22 C C C C C C C C N C C C C H H H H H H H H H

42 Carb2N 32 C C C C C C C C N C C C C C C N C C C C H H H H H H H H H H H H

43 Carb3N 42 C C C C C C C C N C C C C C C N C C C C C C N C C C C H H H H H H H H

44 H H H H H H H Carb4N 52 H H H H H H H H H H H H H H H H H H C C C C N C C C C C

45 C N C C C C C C N C C C C C C N C C C C C C C C Carb5N 62 C C C C C C C C

46 N C C C C C C N C C C C C C N C C C C C C N C C C C C C N C C C C H H H H H H H H H H H H H H H H

47 H H H H H Carb6N 72 C C C C C C C C N C C C C C C N C C C C C C

48 N C C C C C C N C C C C C C N C C C C C C N C C C C H H H H H H H H H H H H H H H H H H H H H H H