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and the DMF was evaporated under vacuum. After removal of the
solvent, the mixture was purified by column chromatography
(Hexanes/EtOAc¼150/1) to give compound 1 (1.299 g, 4.05 mmol,
84%) as yellow solid; mp: 144e145 ꢄC; 1H NMR (400 MHz, CDCl3):
J¼7.8 Hz, 2H), 7.17 (dd, J¼6.4, 5.1 Hz, 2H), 3.94 (s, 4H), 3.44 (d,
J¼2.3 Hz, 2H), 2.30 (t, J¼2.4 Hz, 1H).
5.2.6. 9-(4-(4-((Bis(pyridin-2-ylmethyl)amino)methyl)-1H-1,2,3-
triazol-1-yl)phenyl)-9H-carbazole-3-carbaldehyde (6).18 In a mix-
ture of compound 4 (100 mg, 0.32 mmol) and compound 5
(91.3 mg, 0.385 mmol) in water and t-BuOH (v/v¼3:1, 4 mL), freshly
prepared sodium ascorbate (0.74 mL, 0.2 mol/L) was added, fol-
lowed by the addition of CuSO4 (1.28 mL, 0.05 mol/L) solution. The
heterogeneous mixture was stirred vigorously overnight at room
temperature for about 12 h. Then the raw product was washed with
distilled water, extracted with DCM, and dried with MgSO4. After
removing the solvent with vacuum distillation, the mixture was
purified by column chromatography (CH2Cl2/MeOH¼20:1) to give
compound 6 (82.8 mg, 0.168 mmol, 50%) as yellow solid; mp:
d
8.14 (d, J¼7.8 Hz, 2H), 7.74 (d, J¼8.6 Hz, 2H), 7.46 (m, 2H), 7.40 (dd,
J¼13.5, 4.4 Hz, 4H), 7.32e7.28 (td, J¼7.3, 1.32 Hz, 2H).
5.2.2. 9-(4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)
phenyl)-
9H-carbazole (2).15 A Schlenk flask was charged with compound 1
(600 mg, 1.87 mmol), then bis(pinacolato)diboron (522 mg,
2.06 mmol), PdCl,2DPPF (113 mg, 0.14 mmol), KOAc (550 mg,
5.61 mmol) and dry 1, 4-dioxane (15 mL) were added to the flask
under argon. The mixture was preactivated for 1 h under room
temperature followed by immersing in an oil bath at 80 ꢄC with
stirring for about 20 h until the starting material had completely
disappeared as judged by TLC. The solvent was evaporated under
reduced pressure and purified by column chromatography (Hex-
anes/EtOAc¼200/1) to give compound 2 (546.4 mg, 1.48 mmol,
80%) as pale yellow solid; mp: 173e174 ꢄC; 1H NMR (400 MHz,
72e73 ꢄC; 1H NMR (400 MHz, CDCl3):
d 10.10 (s, 1H), 8.65 (s, 1H),
8.56 (d, J¼4.1 Hz, 2H), 8.19 (d, J¼7.7 Hz, 1H), 8.04 (d, J¼8.5 Hz, 2H),
7.95 (d, J¼8.5 Hz, 1H), 7.69 (dd, J¼17.0, 8.0 Hz, 4H), 7.60 (d, J¼7.7 Hz,
2H), 7.54e7.33 (m, 5H), 7.20e7.10 (m, 2H), 4.01 (s, 2H), 3.92 (s, 4H).
CDCl3):
d
8.14 (d, J¼7.7 Hz, 2H), 8.05 (d, J¼8.2 Hz, 2H), 7.59 (d,
13C NMR (100 MHz, CDCl3):
d 191.60, 158.94, 149.11, 145.37, 144.16,
J¼8.2 Hz, 2H), 7.48e7.36 (m, 4H), 7.33e7.25 (m, 2H), 1.40 (s, 12H).
141.53, 136.81, 136.61, 136.56, 129.80, 128.42, 127.70, 127.27, 123.83,
123.77, 123.47, 123.38, 122.20, 122.10, 121.62, 121.43, 120.83, 110.17,
109.90, 77.40, 77.08, 76.76, 59.59, 53.44, 48.49. HRMS (ESI): m/z
calcd for C34H28N7O [MþH]þ: 550.2355, found: 550.2354.
5.2.3. 9-(4-Azidophenyl)-9H-carbazole (3).16 To a solution of com-
pound 2 (228 mg, 0.617 mmol) in methanol (10 mL), NaN3
(60.22 mg, 0.926 mmol) and Cu(OAc)2 (12.32 mg, 0.0617 mmol)
were added. The mixture was stirred in a 55 ꢄC of oil bath under air
for about 3 h until the starting material had been completely con-
sumed as detected by TLC. The crude yellow oil was then diluted
with EtOAc (150 mL), washed with saturated NaCl solution, and
dried with MgSO4. After removal of the solvent, the mixture was
purified by column chromatography (Hexanes/EtOAc¼150/1) to
give 3 (126 mg, 0.44 mmol, 80%) as a yellow crystals; mp:
5.2.7. HCD.19 To a solution of compound 6(38 mg, 0.07 mmol)in
ethanol (3 mL) were added hemicyanine (36.2 mg, 0.11 mmol) and
piperidine (0.1 mL) under argon. The mixture was refluxed for 15 h
and a red suspension was obtained. Then the suspension was
washed with NaI (0.1 mM) solution and extracted three times with
DCM (30 mL). The organic phases were dried with MgSO4. After
removing the solvent with vacuum distillation, the residue was
purified by column chromatography (CH2Cl2/MeOH¼10:1) to get
HCD (43 mg, 0.05 mmol, 73%) as red solid; mp: 230e235 ꢄC; 1H
111e112 ꢄC; 1H NMR (400 MHz, CDCl3):
(d, J¼8.8 Hz, 2H), 7.40 (td, J¼8.0, 1.2 Hz, 2H), 7.35 (d, J¼8.1 Hz, 2H),
7.30e7.25 (m, 4H).
d
8.15 (d, J¼7.7 Hz, 2H), 7.56
NMR (400 MHz, MeOD):
d
9.11 (d, J¼5.56 Hz, 2H), 9.06 (s, 1H), 8.84
(s, 1H), 8.70 (d, J¼16.0 Hz, 1H), 8.36 (d, J¼7.7 Hz, 1H), 8.22 (d,
J¼8.8 Hz, 3H), 8.11 (td, J¼7.7, 1.6 Hz, 2H), 7.86 (d, J¼8.8 Hz, 2H),
7.83e7.72 (m, 2H), 7.68e7.59 (m, 5H), 7.57e7.49 (m, 2H), 7.47e7.38
(m, 2H), 4.71 (t, J¼7.3 Hz, 2H), 4.39 (s, 2H), 4.28 (d, J¼17.4 Hz, 4H),
2.10e2.00 (m, 2H), 1.91 (s, 6H), 1.27 (m, 2H), 1.14 (t, J¼7.4 Hz, 3H).
5.2.4. 9-(4-Azidophenyl)-9H-carbazole-3-carbaldehyde
(4).17
A
Schlenk flask was charged with dry DMF (5 mL), POCl3 (5 mL) was
then dropping to the flask in ice bathe. The mixture was stirred for
20 min at 0 ꢄC and for another 1 h under room temperature. Then
CHCl3 (5 mL) and compound 3 (254.19 mg, 0.89 mmol) was added
to reflux for about 10 h. The mixture was neutralized by NaOH
solution in ice bath to pH¼10. Then the crude product was diluted
with DCM (150 mL), washed with saturated NaCl solution (30 mL),
and dried with MgSO4. After removal of the solvent by vacuum
distillation, the mixture was purified by column chromatography
(Hexanes/EtOAc¼50/1) to give compound 4 (234 mg, 0.746 mmol,
83%). Dark yellow crystals; mp: 131e132 ꢄC; 1H NMR (400 MHz,
13C NMR (100 MHz, MeOD):
d 181.99, 156.25, 155.30, 148.79, 144.40,
143.93, 143.52, 141.50, 141.25, 140.98, 137.76, 135.90, 129.13, 128.87,
128.31, 127.41, 127.23, 124.84, 124.78, 124.62, 123.29, 122.85, 122.67,
121.83, 120.80, 114.42, 110.54, 110.10, 109.05, 56.85, 52.26, 25.64,
21.75, 9.95. HRMS (ESI): m/z calcd for C48H45N8I [M-I]þ: 733.3767,
found: 733.3766.
5.2.8. CuHCD.6b To a solution of HCD (20 mg, 0.023 mmol) in
ethanol (1 mL) was added CuCl2$2H2O (4 mg, 0.023 mmol) solution
in ethanol (1 mL). The mixture was stirred for about 30 min until
the starting material had been completely consumed as detected by
TLC. 6 mL of Hexane was added to the mixture and the complex was
precipitated from solution. The product was obtained by filter as
red-brown solid (18.4 mg, 0.018 mmol, 80%); mp: 235e240 ꢄC; ESI-
MS: m/z calcd for [MꢀI]þ 868.2421, found: 868.2425.
CDCl3):
d
10.13 (s, 1H), 8.68 (d, J¼1.2 Hz, 1H), 8.21 (d, J¼7.7 Hz, 1H),
7.96 (dd, J¼8.5, 1.5 Hz, 1H), 7.55 (d, J¼8.7 Hz, 2H), 7.49 (t, J¼7.1 Hz,
1H), 7.42e7.33 (m, 3H), 7.30 (d, J¼8.7 Hz, 2H). 13C NMR (100 MHz,
CDCl3):
d 191.64, 144.45, 141.84, 133.30, 129.58, 128.66, 127.53,
127.10, 123.82, 123.61, 123.24, 121.35, 120.75, 120.64, 110.21, 109.91,
77.37, 77.05, 76.73. HRMS (ESI): m/z calcd for C19H13N4O [MþH]þ:
313.1089, found: 313.1095.
5.2.5. (N, N-Bis(2-pyridylmethyl)-N-propargylamine) (5).6a To a so-
lution of Bis (2-picolyl) amine (BPA) (100 mg, 0.5 mmol) in THF
(3 mL) was added propargyl bromide (80% in toluene) (0.1 mL,
0.78 mmol) followed by addition of K2CO3 (207 mg, 1.5 mmol). The
mixture was stirred at room temperature until the starting material
had completely disappeared as judged by TLC. After removing the
solvent under reduced pressure, the residue was purified by col-
umn chromatography (CH2Cl2/MeOH¼40:1) to give compound 5
(118 mg, 0.5 mmol, 100%) as yellow oil. 1H NMR (400 MHz, CDCl3):
5.3. General fluorescence measurements
Stock solution of CuHCD at the concentration of 5ꢁ10ꢀ3 M was
prepared in methanol and stored in a cold place. Absorption spectra
were recorded by Shimadzu UV2600 spectrophotometer and
fluorescence spectra were obtained by FS5 fluorescence spectro-
photometer. All metal ions stock solutions are prepared from their
nitrate, chloride, perchlorate or sulfate (AgNO3, CaCl2, CdSO4$8H2O,
CoCl2$6H2O, CrCl3$6H2O, CuCl2$2H2O, FeCl3$6H2O, LiCl, Mg(ClO4)2,
MnSO4$H2O, Ni(ClO4)2$6H2O, PbCl2, Zn(ClO4)2$6H2O) and all
d
8.57 (dd, J¼4.9, 0.8 Hz, 2H), 7.67 (td, J¼7.7, 1.8 Hz, 2H), 7.53 (d,