D
H.-H. Huang et al.
Letter
Synlett
(3) (a) Wang, L.; Li, P.; Wu, Z.; Yan, J.; Wang, M.; Ding, Y. Synthesis
2003, 2001. (b) Herepoulos, G. A.; Georgakopoulos, S.; Steele, B.
R. Tetrahedron Lett. 2005, 46, 2469.
bined organic layers were washed with brine, dried (MgSO4),
and concentrated to provide the desired primary aromatic
amines.
(4) (a) Nagaraja, D.; Pasha, M. A. Tetrahedron Lett. 1999, 40, 7855.
(b) Pyo, S. H.; Han, B. H. Bull. Korean Chem. Soc. 1995, 16, 81.
(5) (a) Zinin, N. Adv. Synth. Catal. 1842, 27, 140. (b) Zimmermann,
V.; Avemaria, F.; Bräse, S. J. Comb. Chem. 2007, 9, 200.
(6) Barltrop, J. A.; Bunce, N. J. J. Chem. Soc. C 1968, 1467.
(7) Cors, A.; Bonesi, S. M.; Erra-Balsells, R. Tetrahedron Lett. 2008,
49, 1555.
4-Aminobenzonitrile (2a)
Following the General Procedure I, using 4-nitrobenzonitrile
(20.0 mg, 0.135 mmol), provided the title compound as a yel-
lowish powder (12 mg, 75% yield). 1H NMR (300 MHz, CDCl3,
24 °C ): δ = 7.41 (d, J = 8.6 Hz, 2 H), 6.64 (d, J = 8.7 Hz, 2 H), 4.11
(s, 2 H). The 1H NMR spectroscopic data is consistent with the
literature value.12a
(8) Selected references of the challenge in the selective reduction of
dinitrobenzene to the 4-nitroaniline: (a) Chen, Y.; Qiu, J.; Wang,
X.; Xiu, J. J. Catal. 2006, 242, 227. (b) Gowda, D. C.; Mahesh, B.;
Gowda, S. Indian J. Chem., Sect. B: Org. Chem. Incl. Med. Chem.
2001, 40, 75. (c) Pogorelić, I.; Filipan-Litvić, M.; Merkaš, S.;
Ljubić, G.; Cepanec, I.; Litvić, M. J. Mol. Catal. A: Chem. 2007, 274,
202. (d) Zand, Z.; Kazemi, F.; Hosseini, S. Tetrahedron Lett. 2014,
55, 338.
(9) (a) Chen, Y.; Qiu, J.; Wang, X.; Xiu, J. J. Catal. 2006, 242, 227.
(b) Gowda, D. C.; Mahesh, B.; Gowda, S. Indian J. Chem., Sect. B:
Org. Chem. Incl. Med. Chem. 2001, 40, 75. (c) Pogorelić, I.;
Filipan-Litvić, M.; Merkaš, S.; Ljubić, G.; Cepanec, I.; Litvić, M. J.
Mol. Catal. A: Chem. 2007, 274, 202. (d) Zand, Z.; Kazemi, F.;
Hosseini, S. Tetrahedron Lett. 2014, 55, 338.
(10) General Procedure I for the Photoinduced Reduction in i-PrOH
Nitroarene (20 mg) was added into 20 mL i-PrOH. The quartz
tube containing the solution was degassed by ultrasonic cleaner
for 1 h prior to use. The reaction was stirred at r.t. under UV
irradiation (306 nm). Consumption of starting material was
monitored by TLC. Solvent was removed under reduced pres-
sure, and the crude mixture was transferred to a separatory
funnel containing 1 M HCl. The aqueous layer was extracted
two times with CH2Cl2. The aqueous layer was then basified
using 1 N NaOH and extracted two times with EtOAc. The com-
(11) General Procedure II for the Photoinduced Reduction in THF
Nitroarene (50 mg) was added into 25 mL THF. The quartz tube
containing the solution was degassed by ultrasonic cleaner for 1
h prior to use. The reaction was stirred at r.t. under UV irradia-
tion (306 nm). Consumption of starting material was monitored
by TLC. The reaction mixture was transferred to a flask which
was contained Al2O3 (5 g) and then reflux until the intermediate
was consumed. Solvent was removed under reduced pressure,
and the crude mixture was transferred to a separatory funnel
containing 1 M HCl. The aqueous layer was extracted two times
with CH2Cl2. The aqueous layer was then basified using 1 N
NaOH and extracted two times with EtOAc. The combined
organic layers were washed with brine, dried (MgSO4), and con-
centrated to provide the desired primary aromatic amines.
3-Aminobenzonitrile (2b)
Following the General Procedure II, using 3-nitrobenzonitrile
(50.0 mg, 0.338 mmol), provided the title compound as a yel-
lowish powder (27 mg, 66% yield). 1H NMR (300 MHz, CDCl3,
24 °C): δ = 7.22 (t, 1 H, J = 7.9 Hz), 7.02 (d, 1 H, J = 7.6 Hz), 6.90–
6.85 (m, 2 H), 3.85 (s, 2 H). The 1H NMR spectroscopic data is
consistent with the literature value.12b
(12) (a) Orlandi, M.; Tosi, F.; Bonsignore, M.; Benaglia, M. Org. Lett.
2015, 17, 3941. (b) Papadas, I. T.; Fountoulaki, S.; Lykakis, I. N.;
Armatas, G. S. Chem. Eur. J. 2016, 22, 4600.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2017, 28, A–D