1-Substituted Benzimidazoles
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aqueous phase was extracted with CH2Cl2 (2ϫ20 mL), and the
combined organic phases were washed with brine, dried with
Na2SO4 and concentrated to give a crude product, which was puri-
fied by flash chromatography on silica gel.
1-Benzyl-1H-benzo[d]imidazole (4a):[19] Compound 4a (283 mg,
68%) was obtained from 2-bromophenyl isocyanide (1-Br) (364 mg,
2 mmol) and benzylamine (2a) (214 mg, 2 mmol) according to the
GP, after column chromatography (CH2Cl2/MeOH, 20:1; Rf
=
0.27) as a colorless solid, m.p. 115–116 °C (ref.[19] 116–117 °C). H
NMR (300 MHz, CDCl3): δ = 7.93 (s, 1 H, N=CH), 7.83 (d, J =
7.2 Hz, 1 H, Ar-H), 7.35–7.21 (m, 6 H, Ar-H), 7.16 (m, 2 H, Ar-
H), 5.32 (s, 2 H, CH2) ppm. 13C NMR (75.5 MHz, CDCl3): δ =
144.2 (C), 135.4 (CH), 128.9 (CH), 128.5 (C), 128.2 (CH), 127.4
(C), 127.0 (CH), 123.0 (CH), 122.0 (CH), 120.4 (CH), 110.0 (CH),
48.7 (CH2) ppm. MS (70 eV, EI): m/z (%) = 208.1 (74) [M+], 91.1
1
(100). IR (KBr): ν = 3010, 2943, 2154, 1609, 1466, 1184, 1076,
˜
+
753, 720, 694 cm–1. HRMS (ESI): calcd. for C14H13N2 [M + H+]
209.10732; found 209.10730.
3-Benzyl-3H-thieno[2,3-d]imidazole (7a): Compound 7a (210 mg,
49%) was obtained from 2-bromo-3-isocyanothiophene (6)
(376 mg, 2 mmol) and benzylamine (2a) (214 mg, 2 mmol) accord-
ing to the GP, after column chromatography (CH2Cl2/MeOH, 40:1;
Rf = 0.30) as a colorless solid, m.p. 102–103 °C. 1H NMR
(300 MHz, CDCl3): δ = 7.72 (s, 1 H, NCH), 7.36 (m, 3 H, Ph),
7.27 (m, 2 H, Ph), 7.12 (d, J = 5.3 Hz, 1 H, thienyl-H), 6.92 (d, J
= 5.3 Hz, 1 H, thienyl-H), 5.19 (s, 2 H, CH2) ppm. 13C NMR
(75.5 MHz, CDCl3, APT): δ = 148.7 (C), 141.8 (CH), 134.1 (C),
131.6 (C), 129.0 (CH), 128.7 (CH), 128.1 (CH), 120.7 (CH), 116.6
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˜
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2
1354, 1252, 1188, 1092, 1035, 907, 734 cm–1. MS (EI): m/z (%) =
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Supporting Information (see footnote on the first page of this arti-
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1
of H and 13C NMR spectra.
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Acknowledgments
This work was supported by the Land Niedersachsen. A. V. L. is
indebted to the Degussa-Stiftung (Evonik Industries AG) for a
graduate student fellowship.
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Received: July 22, 2009
Published Online: September 11, 2009
Eur. J. Org. Chem. 2009, 5138–5141
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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