2.1. Materials
Dichloromethane (DCM), tetrahydrofuran (THF), phenol, sodium hydride (NaH) (60% dispersion in mineral oil), n-hexane, 2-naphthol, magnesium sulphate (MgSO4), absolute ethanol (EtOH), sodium sulphate (Na2SO4), ammonium acetate, 4-hydroxybenzaldehyde, ammonia solution, 1,10-phenanthroline, potassium bromide (KBr), acetic acid, sulphuric acid (H2SO4), nitric acid (HNO3), THF-d8 were purchased from Merck. 1,10-Phenanthroline-5,6-dione was supplied from Sigma Aldrich. All of the solvents were purified by conventional methods.
The poly(methyl methacrylate) (PMMA) (MW: 120,000), ethylcellulose (EC) (ethoxy content of 46%), nonadecafluorodecanoic acid (PFC), room temperature ionic liquid (RTIL), 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and bis-(2-ethylhexyl)phthalate (DOP) were supplied from Sigma Aldrich to obtain thin films.
To record luminescence spectra, 10 mm path length quartz cells with septum were supplied from Hellma. Nitrogen and oxygen gas cylinders were 99.99% pure and supplied from Linde Gas Company, Izmir.
2.3. Synthesis and characterization
The starting compounds, 11,12-dichloro-dipyrido [3,2-a: 2 ', 3'-c] phenazine (Cl2dppz) [16, 17] and Ir-dimer [18–20] were synthesized according to the literature. Synthetic pathways (See Scheme S1 and S2) and characterization (See Figs S1-S4) of these compounds were given as in a supplementary file. Synthetic pathways of L1-4 ligands and Ir-1, Ir-2, Ir-3, Ir-4 complexes were given in Scheme 1 and Scheme 2, respectively. The same synthetic procedure was employed for obtaining L1-L4 complexes. So experimental details were given for only L1. Also, the similar synthesis process was used for producing Ir-1-Ir-4 compounds, and experimental data were given for only Ir-1.
2.3.1. Synthesis of L1
Cl2dppz (5 mmol), phenol (10 mmol) and K2CO3 (15 mmol) reacted in dry DMF (25 mL) under argon atmosphere by refluxing for 2 days. The reaction mixture was cooled to room temperature and filtered off and the solid phase was washed with water. The crude solid product was purified by preparative TLC on silica with DCM:EtOH (30:1) as the eluent (60% yield). Anal. Calc. for C30H18N4O2; C, 77.24; H, 3.89; N, 12.01. Found: C, 77.54; H, 3.99; N, 12.10 %. MALDI-TOF-MS (m/z): [M]+, 466.97 (cal cd. 466.14). FT-IR (ATR /cm− 1): 3070 (ArC-H), 3003 (C-H) 1589 (ArC = C), 1470(C = N), 1254-1214-(C-O-C), 1070 − 1024 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.48 (d, 2H, CH), 9.24 (t, 2H, CH), 7.73 (m, 2H, CH), 7.61 (s, 2H, CH), 7.53 (m, 4H, CH), 7.32 (m, 6H, CH).
2.3.2. Synthesis of L2
The crude solid product was purified by preparative TLC on silica with DCM:EtOH (25:1) as the eluent (75% yield). Anal. Calc. for C32H22N4O4 ; C, 72.99; H, 4.21; N, 10.64. Found: C, 71.83; H, 4.08; N, 10.49 %. MALDI-TOF-MS (m/z): [M]+ 526.31 (calcd. 526.16). FT-IR (ATR /cm− 1): ʋ 3096 (ArC-H), 2839 (C-H) 1573 (ArC = C), 1472 (C = N), 1251-1208-(C-O-C), 1070 − 1022 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.48 (d, 2H, CH), 9.24 (t, 2H, CH), 7.75 (t, 2H, CH), 7.48 (t, 2H, CH), 7.29 (t, 4H, CH), 7.08(t, 4H, CH), 3.92 (t, 6H, CH3).
2.3.3. Synthesis of L3
The crude solid product was purified by preparative TLC on silica with DCM:EtOH (40:1) as the eluent (70% yield). Anal. Calc. for C30H16N4O2 ; C, 71.71; H, 3.21; N, 7.56. Found: C, 71.85; H, 3.28; N, 7.70 %. MALDI-TOF-MS (m/z): [M]+ 502.95 (calcd. 502.12). FT-IR (ATR /cm− 1): ʋ 3077 (ArC-H), 2925 (C-H), 1570 (ArC = C), 1469 (C = N), 1255 (C-O-C), 1089 (C-O). 1H NMR (500 MHz, CDCl3) ™/ppm: 9.49 (d, 2H, CH), 9.24 (t, 2H, CH), 7.74 (t, 2H, CH), 7.54 (t, 2H, CH), 7.28 (t, 4H, CH), 7.23(t, 4H, CH).
2.3.4. Synthesis of L4
The crude solid product was purified by preparative TLC on silica with DCM:EtOH (35:1) as the eluent (65% yield). Anal. Calc. for C32H22N4O2 ; C, 77.22; H, 4.48; N, 11.33. Found: C, 77.30; H, 4.29; N, 11.20%. MALDI-TOF-MS (m/z): [M]+ 494.71 (calcd. 494.17). FT-IR (ATR /cm− 1): ʋ 3066 (ArC-H), 2922 (C-H) 1575 (ArC = C), 1470(C = N), 1256-1212-(C-O-C), 1072 − 1032 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.48 (d, 2H, CH), 9.22 (t, 2H, CH), 7.72 (t, 2H, CH), 7.54 (d, 2H, CH), 7.33(d, 4H, CH), 7.22(d, 4H, CH), 2.46 (s, 6H, CH3).
2.3.5. Synthesis ofIr-1
Ir-dimer (10 mmol) and L1 (21 mmol) and 30 mL EtOH was added to a flask and refluxed at night under an inert medium. The mix was cooled to 25 C and the solvent was removed under pressure. The obtained precipitate was washed by CH2Cl2/EtOH mixture several times and dried to give Ir-1 as solid (75 % yield.) Anal. Calc. for C56H36F6IrN6O4; C, 57.83; H, 3.12; N, 7.23. Found: C, 57.75; H, 3.20; N, 7.45 %. MALDI-TOF-MS (m/z): [M + H]+,1164.56 (calcd. 1163.13). FT-IR (ATR /cm− 1): ʋ 3070 (ArC-H), 1560 (ArC = C), 1480 (C = N), 1113 − 1014 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.76 (t, 2H, ArH), 8.28 (dd, 2H, ArH), 8.28 (d, 1H), 8.02 (dd, 2H, ArH), 7.86 (s, 1H, ArH), 7.61–7.49 (m, 8H, ArH), 7.44–7.31 (m, 8H, ArH), 7.22 (d, 1H, ArH), 7.20 (d, 1H, ArH), 6.87 (d, 1H, ArH), 6.86 (d, 1H, ArH), 6.58 (d, 1H, ArH), 6.56 (d, 1H, ArH), 3.98 (s, 6H, CH3).
2.3.6. Synthesis ofIr-2
Ir-2 was obtained as solid (65 % yield.) Anal. Calc. for C58H40F6IrN6O6; C, 56.95; H, 3.30; N, 6.87. Found: C, 56.65; H, 3.25; N, 6.95 %. MALDI-TOF-MS (m/z): [M + H]+,1224.10 (calcd. 1223.25). FT-IR (ATR /cm− 1): ʋ 3067 (ArC-H), 1559 (ArC = C), 1475 (C = N), 1112 − 1015 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.47 (d, 2H, ArH), 8.27 (d, 2H, ArH), 8.01 (m, 2H, ArH), 7,86 (s, 2H, ArH), 7.49 (d, 4H, ArH), 7.43 (d, 2H, ArH), 7.30 (t, 4H, ArH), 7.21 (d, 2H, ArH), 7.10 (d, 4H, ArH), 6.83 (dd, 2H, ArH), 6.57 (d, 2H, ArH), 3.98 (s, 6H, AO-CH3), 3.92 (s, 6H, O-CH3).
2.3.7. Synthesis ofIr-3
Ir-3 was obtained as solid (60 % yield.) Anal. Calc. for C56H34F8IrN6O4; C, 56.09; H, 2.86; N, 7.01. Found: C, 56.15; H, 2.95; N, 6.90 %. MALDI-TOF-MS (m/z): [M]+,1199.13 (calcd. 1199.21). FT-IR (ATR /cm− 1): ʋ 3100 (ArC-H), 1560 (ArC = C), 1480 (C = N), 1110 − 1020 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.71 (d, 2H, ArH), 8.27 (d, 2H, ArH), 7.98 (t, 1H, ArH), 7,87 (s, 2H, ArH), 7.70 (d, 2H, ArH), 7.49 (m, 6H, ArH), 7.27 (m, 6H, ArH), 7.10 (m, 4H, ArH), 6.77 (m, 1H, ArH), 6.54 ppm (dd, 2H, ArH), 3.94 (s, 6H, O-CH3).
2.3.8. Synthesis ofIr-4
Ir-4 was obtained as solid (80 % yield.) Anal. Calc. for C56H40F6IrN6O4; C, 58.48; H, 3.38; N, 7.06. Found: C, 58.40; H, 3.25; N, 7.30 %. MALDI-TOF-MS (m/z): [M]+,1191.23 (calcd. 1191.26). FT-IR (ATR /cm− 1): ʋ 3070 (ArC-H), 2910 − 2850 (CH3), 1559 (ArC = C), 1480 (C = N), 1115 − 1021 (C-O). 1H NMR (500 MHz, CDCl3) δ (ppm): 9.74 (d, 2H, ArH), 8.27 (d, 2H, ArH), 8.02 (t,2, ArH), 7,86 (s, 2H, ArH), 7.58–7.16 (m, 16H, ArH), 6.84 (d, 2H, ArH), 6.57 (d, 2H, ArH), 3.98 ppm (s, 6H, O-CH3), 2.47 (s, 6H, O-CH3).