Supplementary Information for

Molecular design of azo-carbazole monolithic dyes for updatable full-colour holograms

Kenji Kinashi1,Takahiro Fukami2,Yuki Yabuhara2,Satsuki Motoishi3, Wataru Sakai1,Masuki Kawamoto4, Takafumi Sassa4, Naoto Tsutsumi1*

1Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-8585, Japan

2Department of Macromolecular Science and Engineering, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-8585, Japan

3Master’s Program for Innovative Materials, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo, Kyoto 606-8585, Japan

4Riken, 2-1 Hirosawa, Wako Saitama 351-0198, Japan

NACzE, CACzE and AACzE were synthesized from carbazole, AmACzE were synthesized from NACzE, FACzE was synthesized fromAmACzE,HACzE was synthesized from 4-nitroaniline, and MACzEwere synthesized from HACzE. The followings are the detailed synthesis procedures for all compounds. Schematic procedure is also shown in Scheme S1, which is the same as Scheme 1 in the main manuscript.In Scheme S1, the synthetic intermediates are numbered.

9H-Carbazole-9-ethanol (1)

NaH (31.20 g, 0.78 mmol) was slowlyadded to a solution of carbazole (108.7 g, 0.65 mol) in dry THF (1.8 L), and the mixture was stirred for 1 hunder an argon atmosphere.To this reaction mixture 2-(2-bromoethoxy)tetrahydropyrane (203.9, 0.97 mol) was added, and the reaction mixture was carefully heated at 60 °C for 8 h. The mixture was filtered with silica gel, and washed with THF.The filtered solution was concentrated in vacuo.p-Toluenesulfonic acid (pTSA) (1.1g, 6.38 mmol) was added to a solution of the intermediate product in methanol(1.5 L), and the mixture was refluxed for 0.5 h. The mixture was concentration in vacuo, and purified by column chromatography on silica gel (eluent:toluene/heptane, 10/1, v/v) and recrystallized from heptane to give 9H-carbazole-9-ethanol (1) (60.9 g, 0.29 mol, 44.4% yield).

3-[(4-Nitrophenyl)azo]-9H-carbazole-9-ethanol (NACzE)

An aqueous solution (H2O 200mL) containing NaNO2 (27.44 g, 0.40 mol) was slowly added to an aqueous acid solution (H2O 1.6 L and conc. HCl 270 mL) containing 4-nitroaniline (52.34 g, 0.38 mol) and then stirred in a salt-ice bath (–2 °C) for 1h.A solution of 9H-carbazole-9-ethanol (1) (80.00 g, 0.38 mol) in dichloromethane (1.2 L)wasslowly added to the mixture, and then warmed slowly to roomtemperature and stirred continuously for 24 h. The solution was extracted, and the organic layer was dried over anhydrousMgSO4 and concentrated in vacuo.The crude product was recrystallized from THF/MeOH to give NACzE as red crystals (116.2 g, 85.1%).

85.1% yield. Product: red crystals; mp 208.0-209.0C:FT-IR(KBr pellet, cm-1): 1518 (NO antisymmetric stretching), 1338 (NO symmetric stretching). LC-MS calcd (found): m/z360.37 (362.0) [M+].1H-NMR (600 MHz, CDCl3, ppm): δ =8.76 (d, 1H, 4-Cz, J= 1.5 Hz), 8.39(d, 2H, J=8.7 Hz,3,5-ArNO2), 8.20 (d, 1H, J=7.9 Hz, 5-Cz), 8.18 (dd, 1H, J= 1.9 Hz,J=8.7 Hz, 2-Cz), 8.06 (d, 2H, J=8.7 Hz, 2,6-ArNO2), 7.59 (d, 1H, J=8.7 Hz, 1-Cz), 7.56-7.52 (m, 2H,7,8-Cz), 7.35 (td, 1H,J= 1.5 Hz, J= 7.9 Hz,6-Cz), 4.56 (t, 2H, J=5.3 Hz, NCH2), 4.15 (q, 2H, J=5.3 Hz, CH2OH), 1.60(t, 1H, J=5.6 Hz, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 156.34, 148.13, 146.58,143.48, 141.56, 126.86, 124.78, 123.65, 123.64, 123.07, 121.51, 120.93,120.59, 117.90, 109.58, 109.41, 61.47, 45.84.Anal. calcdfor C20H16N4O3: C 66.66, H 4.48, N 15.55; found: C 66.80, H 4.51, N15.50.

3-[(4-Cianophenyl)azo]-9H-carbazole-9-ethanol (CACzE)

An aqueous solution (H2O 250 mL) containing NaNO2(21.75 g, 0.32 mol) was slowly added to an aqueous acid solution (H2O 1.2 L and conc. HCl 240 mL)containing 4-aminobenzonitrile (35.44 g, 0.30 mol) and then stirred in a salt-ice bath (–2°C) for 1h.A solution of 9H-carbazole-9-ethanol (1) (63.40 g, 0.3 mol) in dichloromethane (1.2 L) and sodium dodecyl sulfate (1.65 g, 5.72 mmol) wereslowly added to the mixture, and then warmed slowly to roomtemperature and stirred continuously for 24 h. The solution was extracted, and the organic layer was dried over anhydrousMgSO4 and concentrated in vacuo.The crude product was recrystallized from THF/MeOH to give CACzE as red crystals (76.55 g, 74.9%).

74.9% yield. Product:red crystals; mp 195.6-198.8C:FT-IR(KBr pellet, cm-1): 2222 (CN symmetric stretching). LC-MS calcd (found): m/z340.38 (342.0) [M+].1H-NMR (600 MHz, CDCl3, ppm): δ = 8.72 (d, 1H, J= 1.5 Hz, 4-Cz), 8.19(d, 1H, J=7.5 Hz,5-Cz), 8.15 (dd, 1H, J= 1.5 Hz, J=8.7 Hz, 2-Cz), 8.00 (d, 2H, J=8.3 Hz, 3,5-ArCN), 7.80 (d, 2H, J=8.3 Hz, 2,6-ArCN), 7.56 (d, 1H, J=8.7 Hz, 1-Cz), 7.55-7.50 (m, 2H, 7,8-Cz), 7.34 (td, 1H, J= 1.5 Hz, J= 7.1 Hz, 6-Cz), 4.54 (t, 2H, J=5.3 Hz, NCH2), 4.15 (q, 2H, J=5.3 Hz, CH2OH), 1.64(t, 1H, J= 6.0 Hz, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 155.05, 146.44, 143.33,141.54, 133.19, 126.81, 123.62, 123.58, 123.07, 121.42, 120.90, 120.51,118.75, 117.66, 112.91, 109.54, 109.34, 61.44, 45.83. Anal. calcdfor C21H16N4O: C 74.10, H 4.74, N 16.46; found: C 73.72, H 4.72, N16.24.

3-[(4-Acetylphenyl)azo]-9H-carbazole-9-ethanol (AACzE)

An aqueous solution (H2O 25 mL) containing NaNO2 (2.00 g, 29.0mmol) was slowly added to an aqueous acid solution (H2O 100mL and conc. HCl 25 mL) containing 4-acetylaniline (0.95 g, 7.0 mmol) and then stirred in a salt-ice bath (–2 °C) for 1h.A solution of 9H-carbazole-9-ethanol (1) (1.48 g, 7.0mmol) in dichloromethane (100mL)wasslowly added to the mixture, and then warmed slowly to roomtemperature and stirred continuously for 24 h. The solution was extracted, and the organic layer was dried over anhydrousMgSO4 and concentrated in vacuo.The crude product was recrystallized from THF/MeOH to give AACzE as red crystals (0.23 g, 9.0%).

9.0% yield. Product:red crystals; mp 157.0-159.0C:FT-IR(KBr pellet, cm-1): 1664 (CO symmetric stretching). TOF-MS calcd (found): m/z357.41 (357.10) [M+].1H-NMR (600 MHz, CDCl3, ppm): δ =8.63 (s, 1H, 4-Cz), 8.15[d, 1H, J=7.9 Hz,5-Cz], 8.12 (dd, 1H, J= 1.5 Hz, J=8.9 Hz, 2-Cz), 8.02 (d, 2H, J=8.3 Hz, 3,5-ArCOCH3), 7.94 (d, 2H, J=8.3 Hz, 2,6-ArCOCH3), 7.53 (d, 1H, J=8.7 Hz, 1-Cz), 7.51-7.85 (m, 2H, J= 1.5 Hz, J= 6.9 Hz, 7,8-Cz), 4.50 (t, 2H, J=5.3 Hz, NCH2), 4.11 (m, 2H, CH2OH), 1.59(s, 1H, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 197.61, 155.57, 146.57,143.06, 141.55, 137.52, 129.36, 126.66, 123.61, 123.45, 122.54, 121.34,120.84, 120.33, 117.26, 109.52, 109.24, 61.40, 45.88, 26.65.Anal. calcdfor C21H17N3O2: C 73.93, H 5.36, N 11.76; found: C 73.47, H 5.49, N11.34.

3-[(4-Aminophenyl)azo]-9H-carbazole-9-ethanol (AmACzE)

NACzE (1.0 g, 2.8 mmol), reduced Fe (0.8 g, 1.4 mmol) and an aqueous solution (H2O 7.5 mL) containing NH4Cl (3.8 g, 71.3 mmol) were mixed in toluene(30 mL), and the mixture was stirred at 60 °C for 20 h.The solution was warmed to roomtemperature and then mixing the solution with a saturated aqueous NaHCO3 solution and ethylacetate to make the solution weakly basic. The solution was extracted withwater after filtration using a filter paper, and the organic layer was dried over anhydrousMgSO4 and concentrated in vacuo. The crudeproduct was purified by column chromatography on silica gel (eluent: toluene/THF,6/1 v/v) and recrystallzed from ethylacetate/heptane to give AmACzE as red crystals (0.1 g, 0.3 mmol, 11.0%).

11.0% yield. Product:red crystals; mp 144.4-146.4C:FT-IR(KBr pellet, cm-1): 3214 (NH symmetric stretching). TOF-MS calcd (found): m/z330.38 (330.39) [M+].1H-NMR (600 MHz, CDCl3, ppm): δ =8.62 (d, 1H, J=1.5 Hz, 4-Cz), 8.17[d, 2H, J=7.9 Hz,5-Cz], 8.07 (dd, 1H, J= 1.5 Hz, J=8.7 Hz, 2-Cz), 7.85 (d, 2H, J=8.3 Hz, 2,6-ArNH2), 7.52 (d, 1H, J= 9.0 Hz, 1-Cz), 7.50-7.48 (m, 2H, 7,8-Cz), 7.31-7.27 (m, 1H, 6-Cz), 6.77 (d, 2H, 3,5-ArNH2), 4.52 (t, 2H, J=5.6 Hz, NCH2), 4.11 (q, 2H, J=5.3 Hz, CH2OH), 1.62(t, 1H, J=5.3 Hz, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 148.83, 146.83, 145.90,141.93, 141.46, 126.31, 124.63, 123.73, 123.41, 120.98, 120.84, 119.91,115.64, 114.83, 109.22, 108.97, 61.54, 45.78.Anal. calcdfor C20H18N4O2: C 72.71, H 5.49, N 16.96; found: C 72.33, H 5.51, N16.64.

3-[(4-Fluorophenyl)azo]-9H-carbazole-9-ethanol (FACzE)

HBF4 (2.40 g, 11.5 mmol) was dissolved in ethanol (16.1 mL), and stirred in an ice bath for 10 min.To this solution isopentyl nitrite (0.77 g, 6.5 mmol) was added, and the mixture was stirred at r.t. for 10min.A solution of AmACzE (0.80 g, 2.4 mmol) and HBF4 (1.00 g, 4.8 mmol)in ethanol (16.1 mL) keeping the temperature at 0 °C was added to the solution at 0 °C.The mixture was then warmed slowly to roomtemperature and stirred continuously for 5 h. The crudeproduct was filtrated and washed with ethanol and THF to give diazonium salt(2) (80% yield).

The diazonium salt (2) (215 mg, 0.50 mmol) was slowly added dropwise to a dehydrated xylene (16 mL), and stirred at 125 °C under an argon atmosphere for 2 h.The mixture added with THF (50 mL) was purified by column chromatography on ODS silica gel(eluent: acetonitrile/H2O,7/3 v/v) to give FACzE as orange crystals85mg, 0.25 mmol, 50.0%).

50.0% yield. Product:orange crystals; mp 135.6-138.4C:FT-IR(KBr pellet, cm-1): 1229 (CF symmetric stretching). TOF-MS calcd (found): m/z333.36 (334.15) [M+].Product: orange crystals.1H-NMR (600 MHz, CDCl3, ppm): δ =8.69 (d, 1H, J= 1.9 Hz, 4-Cz), 8.19[d, 1H, J=7.3 Hz,5-Cz], 8.13 (dd, 1H, J= 1.9 Hz, J=8.6 Hz, 2-Cz), 7.96 (dd, 2H, J= 8.6 Hz, 4JHF= 5.6 Hz, 2,6-ArF), 7.55 (d, 1H, J=8.7 Hz, 1-Cz), 7.54-7.50 (m, 2H, 7,8-Cz), 7.34-7.30 (m, 1H, 6-Cz), 7.21 (dd, 2H, J= 8.6 Hz, 4JHF= 8.6 Hz, 3,5-ArF), 4.54 (t, 2H, J=5.6 Hz, NCH2), 4.12 (q, 2H, J=5.6 Hz, CH2OH), 1.59(t, 1H, J=5.6 Hz, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 163.07, 149.50, 146.43,142.60, 141.51, 126.56, 124.39, 123.67, 123.46, 121.08, 120.86, 120.19,116.61, 114.83, 109.22, 108.97, 61.52, 45.80.Anal. calcdfor C20H16FN3O: C 72.06, H 4.84, N 12.61; found: C 71.86, H 4.96, N12.39.

3-[(4-Hydroxyphenyl)azo]-9H-carbazole-9-ethanol (HACzE)

4-Nitroaniline (42.32 g, 0.31 mol), iodobenzene (50.00 g, 0.25 mol), CuO (0.25 g, 3.1 mmol), and KOH (13.75 g, 0.25 mol) were dissolved in DMSO (200 mL), and stirred at 110 °C for 18 h. The mixturewas poured into water and extracted with ethylacetate (1.0 L). The organic layer was washed with waterand brine, and the organiclayer was dried over anhydrous MgSO4 and concentrated invacuo.The resulting crude product was purified by columnchromatography on silica gel (eluent: toluene/heptane, 2/1 v/v) to give 4-nitrodiphenylamine (3) (80% yield).

4-nitrodiphenylamine (3) (50.00 g, 0.23 mol) and Pd(CH3COO)2 (5.00 g, 22.7 mmol) were dissolved in AcOH (500 mL), and refluxed with a continuous bubbling of air for 10 days. The mixturewas poured into water (3 L), and the precipitated crudeproduct was separated by filtration.The resulting crude product was purified by columnchromatography on silica gel (eluent: toluene/THF, 20/1 v/v) to give 3-nitrocarbazole(4) (50% yield).

Cs2CO3 (44.22 g, 0.14 mol) was slowlyadded to a solution of 3-nitrocarbazole (24.00 g, 0.11 mol) in dry THF (500mL), and the mixture was stirred for 1 hunder an argon atmosphere.To this reaction mixture 2-(2-bromoethoxy)tetrahydropyrane (28.37 g, 0.14 mol) was added, and the mixture was carefully heated at 60 °C for 8 h. The mixture was filtered with silica gel, and washed with THF.The filtered solution was concentrated in vacuo.p-Toluenesulfonic acid (pTSA) (300 mg, 1.74 mmol) was added to a solution of the intermediate product in methanol(400mL), and the mixture was refluxed for 0.5 h. The mixture was concentration in vacuo, and purified by column chromatography on silica gel (eluent:toluene/heptane, 10/1, v/v) and recrystallized from heptane to give 3-nitro-9H-carbazole-9-ethanol (5)(74.9% yield).

3-nitro-9H-carbazole-9-ethanol (21.50 g, 84.0 mmol), 5%Pd/C(en) (4 g) was dissolved in THF (400 mL), and stirred for 24 hunder H2atmosphere.The residual Pd/C(en) was separated by filtration, and the filtered solution was concentrated in vacuo to give 3-amino-9H-carbazole-9-ethanol (6) (102% yield).

An aqueous solution (H2O 20 mL) containing NaNO2 (5.79 g, 84.0 mmol) was slowly added to a solution (H2O 54mL, DMSO 100 mL and 3N HCl 54 mL) containing 3-amino-9H-carbazole-9-ethanol (6) (18.00 g, 80.0mmol) and then stirred in a salt-ice bath (–2 °C) for 0.5h.An aqueous solution (H2O 300 mL) containing phenol (14.97 g, 0.16 mol) and NaOH (6.68 g, 0.17 mol)was added to the mixture, and then stirred continuouslyin a salt-ice bath (–2 °C) for 2h. The reaction mixture was acidified with 3N HCl, and the upper layer was removed by decantation. The residue was purified by column chromatography on silica gel (eluent:toluene/THF,3/1, v/v) to give HACzEas orange crystals (17.28 g, 62.1%).

62.1% yield. Product:orange crystals; mp 254.1-255.2C (decomp.):FT-IR(KBr pellet, cm-1): 3150 (PhOH symmetric stretching). TOF-MS calcd (found): m/z331.37 (362.37) [CH3OM].1H-NMR (600 MHz, DMSO-d6, ppm): δ =10.10 (s, 1H, ArOH), 8.67[d, 1H, J=1.8 Hz,4-Cz], 8.29 (d, 1H, J=7.7 Hz, 5-Cz), 8.01 (dd, 1H, J= 1.8 Hz, J=8.9 Hz, 2-Cz), 7.83 (d, 2H, J=8.8 Hz, 2,6-ArOH), 7.75 (d, 1H, J=8.8 Hz, 1-Cz), 7.67 (t, 1H, J= 8.3 Hz,8-Cz), 7.50 (t, 1H, J= 7.7 Hz,7-Cz), 7.26 (t, 1H, J= 7.7 Hz, 6-Cz), 6.96 (d, 2H, J=8.6 Hz, 3,5-ArOH), 4.83(t, 1H, J=5.5 Hz, CH2OH), 4.50(t, 2H, J= 5.3 Hz, NCH2), 3.81(q, 2H, J= 5.3 Hz, CH2OH).

3-[(4-Methoxyphenyl)azo]-9H-carbazole-9-ethanol (MACzE)

CH3I (7.54 g, 53.1mmol) was added to a solution of HACzE(16.00 g, 48.3mmol) and K2CO3 (6.67 g, 48.3 mmol) in DMF (160mL), and the mixture was stirred for 18 h. Another CH3I (3.00 g, 21.1mmol) and K2CO3 (3.00 g, 21.7 mmol) were added after stirring for additional 4 h, there was still some starting reagents were left.The mixturewas poured into water (1.6 L) and extracted with a mixed solvent of ethylacetate/THF (10/1 v/v). The organic layer was washed with waterand brine, and the washed organiclayer was dried over anhydrous MgSO4 and concentrated invacuo. The resulting crude product was recrystallized from THF/heptane, and the obtained solid was washed in hot heptane for 1 h to give MACzE as red crystals (15.16 g, 90.9%).

90.9% yield. Product:red crystals; mp 121.9-122.8C:FT-IR(KBr pellet, cm-1): 1246 (COC antisymmetric stretching), 1030 (COC symmetric stretching). TOF-MS calcd (found): m/z345.39 (346.17) [M+].1H-NMR (600 MHz, CDCl3, ppm): δ =8.63 (d, 1H, J= 1.5 Hz, 4-Cz), 8.16[d, 1H, J=7.9 Hz,5-Cz], 8.07 (dd, 1H, J= 1.5 Hz, J=8.6 Hz, 2-Cz), 7.94 (d, 2H, J=8.7 Hz, 2,6-ArOCH3), 7.50-7.45 (m, 3H, 7,8-Cz), 7.28 (m, 1H,6-Cz), 7.02 (d, 2H, J= 9.0 Hz, 3,5-ArOCH3), 4.48 (t, 2H, J= 5.3 Hz, NCH2), 4.06 (q, 2H, J=5.6 Hz, CH2OH), 3.89 (q, 2H, J= 6.0 Hz, ArOCH3), 1.71(t, 1H, J= 6.0 Hz, CH2OH).13C-NMR (150 MHz, CDCl3, ppm): δ = 161.44, 147.28, 146.59,142.19, 141.44, 126.37, 124.28, 123.64, 123.36, 120.91, 120.80, 119.98,116.04, 114.22, 109.27, 109.01, 61.42, 55.56, 45.74.Anal. calcdfor C21H19N3O2: C 73.03, H 5.54, N 12.17; found: C 72.96, H 5.38, N12.28.

Scheme S1Synthetic procedure for ACzEs.

Figure S113C-NMR spectraofACzEs.

Figure S2Schematic representation of the angular selectivity obtained with different types of writing beams. M = mirror, MF =Flipper optical mount, L = lens, BS = beam splitter, PBS = polarizing beamsplitter, ND = neutral density filter, D = photodiode, and λ /2 = half wave plate. The recording beam and reading beam are p-polarized light. Laser sources for recording: 25 mW diode-pumped solid-state (DPSS) lasers BluesTM at 473 nm, CalypsoTM at 491 nm, SambaTM at 532 nm, JiveTM at 561 nm, and MamboTM at 594 nm (Cobolot, Sweden) and a 10 mW He-Ne laser at 632.8 nm (CVI Melles Griot, USA). Probe laser for reading: a 10 mW He-Ne laser at 632.8 nm (Lasos, Germany).