Molecules 2021, 26, 1857
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added and reagents were stirred under reflux for 30 min under argon. 8-Nitroquinoline
4a, 4b, or 4d (4.52 mmol), respectively was then added to the reaction mixture, which was
refluxed overnight. After the evaporation of the solvent to give a solid, water (20 mL) and
CH2Cl2 (100 mL) were added. The organic layer was separated and the aqueous layer was
extracted with CH2Cl2 (4
×
50 mL). The combined organic layers were dried over MgSO4.
After solvent evaporating, the crude product was purified by column chromatography on
silica gel using methanol/dichloromethane as eluent to afford a crude solid, and finally
crystallization from a mixture of CH2Cl2 and hexane to yield solids as follows:
9-(8-Nitroquinolin-7-yl)-9H-carbazole (5a) 0.11 g (0.3 mmol, 7%); mp = 160–163 ◦C; 1H-
NMR (CDCl3, 500.2 MHz) δ
= 7.20 (dt, 3JH,H = 8.1 Hz, 4JH,H = 0.9 Hz, 2H, aromatic), 7.32
(ddd, 3JH,H =8.1 Hz, 4JH,H = 7.2 Hz, 4JH,H = 1.0 Hz, 2H, aromatic), 7.40 (ddd, 3JH,H =8.3 Hz,
4JH,H = 7.2 Hz, 4JH,H = 1.3 Hz, 2H, aromatic), 7.60 (d, 3JH,H = 8.7 Hz, 1H, aromatic), 7.69
(dd, 3JH,H = 8.4 Hz, 4JH,H = 4.3 Hz, 1H, aromatic), 8.12 (ddd, 3JH,H = 7.8 Hz, 4JH,H = 1.3 Hz,
4JH,H = 0.8 Hz, 2H, aromatic), 8.16 (d, 3JH,H = 8.7 Hz, 1H, aromatic), 8.39 (dd, 3JH,H = 8.4
Hz, 4JH,H = 1.7 Hz, 1H, aromatic), 9.14 (dd, 3JH,H = 4.3 Hz, 4JH,H = 1.7 Hz, 1H, aromatic);
13C{1H}-NMR (CDCl3; 125.8 MHz)
δ
= 110.2, 120.6, 121.2, 123.6, 124.3, 126.6, 127.8, 128.8,
130.5, 131.3, 136.1, 140.5, 141.5, 148.0, 153.3; HRMS (IT-TOF): m/z Calcd for C21H14N3O2
(M + H)+ = 340.1086, Found 340.1094; UV-Vis (methanol;
(nm) (log )): 329 (3.74), 315
λ
ε
(3.74), 287 (4.21), 225 (4.88), 206 (4.69); IR (KBr):
ν = 3060, 2925, 1731, 1541, 1450, 1225, 757
cm−1; CCDC (The Cambridge Crystallographic Data Centre) 2048038.
(Z)-7-(9H-Carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one (5b) 0.24 g (0.7 mmol, 16%);
mpdec. = 210–211 ◦C; 1H-NMR (CDCl3, 500.2 MHz)
δ = 6.97 (s, 1H, aromatic), 7.31 (ddd,
3JH,H = 8.0 Hz, 4JH,H = 4.7 Hz, 4JH,H = 3.4 Hz, 2H, aromatic), 7.42 (dd, 3JH,H = 3.6 Hz, 4JH,H
= 1.0 Hz, 4H, aromatic), 7.84 (dd, 3JH,H =8.0, 4JH,H = 4.9, 1H, aromatic), 8.10 (dt, 3JH,H =7.8,
4JH,H = 1.0, 2H, aromatic), 8.81 (dd, 3JH,H =8.0, 4JH,H = 1.8 Hz, 1H, aromatic), 8.88 (dd, 3JH,H
=4.9 Hz, 4JH,H = 1.8 Hz, 1H, aromatic), 17.76 (s, 1H, OH); 1H-NMR (DMSO-d6, 500.2 MHz)
δ
= 7.03 (s, 1H, aromatic), 7.29 (dd, 3JH,H = 7.4 Hz, 2H, aromatic), 7.43 (dd, 3JH,H = 7.3 Hz,
2H, aromatic), 7.56 (d, 3JH,H = 8.2 Hz, 2H, aromatic), 8.03 (dd, 3JH,H = 8.0 Hz, 4JH,H = 4.9
Hz, 1H, aromatic), 8.21 (d, 3JH,H =7.7 Hz, 2H, aromatic), 8.74 (dd, 3JH,H =8.0 Hz, 4JH,H
1.5 Hz, 1H, aromatic), 9.07 (dd, 3JH,H = 4.9 Hz, 4JH,H = 1.5 Hz, 1H, aromatic), 17.41 (s, 1H,
=
OH); 1HNMR (DMSO-d6/KOD, 500.2 MHz) = 7.19–7.33 (m, 3JH,H = 7.0 Hz, 4JH,H = 0.8
δ
Hz, 4H, aromatic), 7.40 (t, 3JH,H = 7.4 Hz, 2H, aromatic), 7.55 (dd, 3JH,H = 7.9 Hz, 4JH,H
=
=
4.4 Hz, 1H, aromatic), 8.23 (d, 3JH,H =7.6 Hz, 2H, aromatic), 8.66 (dd, 3JH,H =8.1 Hz, 4JH,H
2.0 Hz, 1H, aromatic), 8.94 (bs, 1H, aromatic); 13C{1H}-NMR (CDCl3; 125.8 MHz)
δ
= 111.2,
120.5, 121.2, 124.6, 126.0, 126.3, 126.4, 126.7, 136.7, 140.2, 141.3, 147.6, 148.1, 150.2, 182.4;
MS (IT-TOF): m/z (relative intensity (rel. int.) (M + H)+ = 340.1091 (100%); (M H2O)+ =
322.0984 (23%);(M + Na)+ = 362.0913 (9%); HRMS (IT-TOF): m/z Calcd for C21H14N3O2 (M
+ H)+ = 340.1086, Found 340.1091; UV-Vis (1 M KOH;
(nm) (log )): 406(4.22), 330 (3.83),
318 (3.86), 287 (4.10), 276 (4.13), 234 (4.63); (DMF; (nm) (log )): 430 (3.56), 330 (4.13), 317
(4.18); (DMSO; (nm) (log )): 430 (3.00), 331 (3.77), 320 (3.81), 290 (4.03); (ACN; (nm)
(log )): 444 (2.64), 330 (3.63), 317 (3.71), 289 (3.78), 228 (4.10); (methanol; (nm) (log )): 453
(3.22), 328 (4.13), 317 (4.17), 287 (4.37), 228 (4.69); (THF; (nm) (log )): 459(3.18), 330 (4.11),
−
λ
ε
λ
ε
λ
ε
λ
ε
λ
ε
λ
ε
318 (4.15), 288 (4.34), 239 (4.55); (CDCl3; λ (nm) (logε)): 478(3.35), 329 (4.23), 318 (4.24), 289
(4.42); IR (KBr): ν = 3045, 2927, 1649, 1601, 1447, 1298, 750, 719 cm−1; CCDC 2048039.
9-(8-isoPropyl-2-((8-isopropyl-2-methyl-5-nitroquinolin-6-yl)methyl)-5-nitrosoquinolin-6-yl)-
◦
1
9H-carbazole (5d) 0.61 g (1.0 mmol, 44%); mp = 290.1–291.3 C; H-NMR (CDCl3, 500.2
MHz) δ
= 1.48 (d, 3JH,H = 6.8 Hz, 6H, CH(CH3)2), 1.56 (d, 3JH,H = 7.0 Hz, 6H, CH(CH3)2),
2.80 (s, 3H, CH3), 4.24 (septet,3JH,H = 6.8 Hz, 1H, CH), 4.47 (septet,3JH,H = 6.8 Hz, 1H,
CH), 7.26 (s, 2H, aromatic), 7.36 (dt,3JH,H = 7.1 Hz, 4JH,H = 0.7 Hz, 2H, aromatic), 7.41–7.47
(m, 3H, aromatic), 7.80 (s, 1H, aromatic), 8.17 (d,3JH,H = 7.8 Hz, 2H, aromatic), 8.50 (s,
2H, aromatic), 8.54 (s, 1H, aromatic), 8.77 (d,3JH,H = 8.1 Hz, 1H, aromatic); 13C{1H}-NMR
(CDCl3; 125.8 MHz)
δ = 23.1, 23.3, 25.6, 27.9, 28.6, 109.6, 115.3, 115.6, 116.6, 120.6, 120.7,
121.1, 121.3, 122.2, 124.1, 126.5, 126.6, 129.4, 132.1, 132.4, 140.9, 143.6, 144.9, 148.49, 148.54,
149.4, 154.1, 156.4, 160.2, 160.6; MS (ES-TOF): m/z (rel. int.) M+ = 606.2502 (100%), (9-(8-