N. Barbero et al. / Tetrahedron 64 (2008) 7283–7288
7287
1684 (CO); 1H NMR (300 MHz, DMSO-d6) (
d
, ppm): 1.18 (t, J¼7.1 Hz,
NH); 13C NMR (75 MHz, DMSO-d6) (
d
, ppm): 98.2 (d, J¼28.5 Hz),
3H, CH3), 3.81 (q, J¼7.0 Hz, 2H, CH2), 6.88–7.05 (m, 3H, Harom), 7.11
108.1 (d, J¼24.2 Hz), 109.2 (d, J¼9.3 Hz), 126.1, 128.0, 129.7 (CH),
126.4, 129.1 (d, J¼21.6 Hz), 134.3, 153.4 (C), 158.1 (d, J¼235.3 Hz, C);
MS (EI) m/z: 229 (Mþ1, 2), 228 (M, 26), 199 (13), 137 (12), 121 (11),
95 (18), 83 (11), 81 (56), 69 (100). HRMS (EI): calculated for
(d, J¼5.7 Hz, 1H, Harom), 10.81 (br s, 1H, NH); 13C NMR (75 MHz,
DMSO-d6) (d, ppm): 13.6 (CH3), 34.7 (CH2), 107.7, 108.8, 120.6, 120.8
(CH), 128.4, 129.9, 154.0 (C); MS (EI) m/z: 163 (Mþ1, 1), 162 (16), 147
(15), 119 (14), 84 (10); HRMS (EI): calculated for C9H10N2O,
162.0793; found, 162.0793.
C13H9FN2O, 228.0699; found, 228.0701.
4.1.18. 1-Phenyl-5-(trifluoromethyl)-1,3-dihydrobenzoimidazol-2-
one (2r)
4.1.13. 1-(Butyl)-1,3-dihydrobenzoimidazol-2-one (2m)
The same procedure was applied to 1-(2-bromophenyl)-1-
(ethyl)urea 1m (138.9 mg, 0.51 mmol) and CuI (8.5 mg,
0.044 mmol) to afford 2m (58.8 mg, 60%) as a white powder. Mp:
The same procedure was applied to 1-(2-bromo-4-trifluoro-
methylphenyl)-1-(phenyl)urea 1r (104.0 mg, 0.29 mmol) and CuI
(4.6 mg, 0.024 mmol) to afford 2r (43.9 mg, 44%) as a white powder.
132–134 ꢁC (hexane); IR (film) (
NMR (300 MHz, CDCl3) (
n
, cmꢂ1) 3178 (NH), 1696 (CO); 1H
Mp: 215–216 ꢁC (hexane); IR (film) (
1H NMR (300 MHz, DMSO-d6) (
arom), 7.26 (s, 1H), 7.35 (dd, J¼16.4, 9.0 Hz, 1H, Harom), 7.45–7.67
(m, 5H, Harom), 10.09 (br s, 1H, NH); 13C NMR (75 MHz, DMSO-d6) (
n
, cmꢂ1) 3132 (NH), 1708 (CO);
, ppm): 7.11 (d, J¼7.8 Hz, 1H,
d
, ppm): 0.97 (t, J¼7.3 Hz, 3H, CH3), 1.36–
d
1.48 (m, 2H, CH2), 1.71–1.81 (m, 2H, CH2), 3.91 (t, J¼7.3 Hz, 2H, CH2),
7.00 (dd, J¼5.8, 3.2 Hz, 1H, Harom), 7.04–7.09 (m, 2H, Harom), 7.13–
7.19 (m, 1H, Harom), 10.93 (br s, 1H, NH); 13C NMR (75 MHz, CDCl3)
H
d
,
ppm): 106.1 (q, J¼3.65 Hz), 108.7, 118.8 (q, J¼4.1 Hz), 126.6, 128.4,
130.0 (CH), 122.7 (q, J¼31.9 Hz), 125.1 (q, J¼271.3 Hz, CF3), 129.2,
133.6, 134.3, 153.8 (C); MS (EI) m/z: 279 (Mþ1, 3), 278 (M, 100), 249
(25). HRMS (EI): calculated for C14H9F3N2O, 278.0667; found,
278.0674.
(d, ppm): 13.7 (CH3), 20.0, 30.4, 40.5 (CH2), 107.7, 109.7, 120.9,
121.2 (CH),128.2,130.0,156.0 (C); MS (EI) m/z: 191 (Mþ1, 2),190 (M,
62), 173 (19), 148 (34), 134 (100), 119 (58), 106 (13). HRMS (EI):
calculated for C11H14N2O, 190.1106; found, 190.1098.
4.1.14. 1-(Butyl)-4-(trifluoromethyl)-1,3-dihydrobenzoimidazol-2-
one (2n)
The same procedure was applied to 1-(2-bromo-4-trifluoro-
methylphenyl)-1-(butyl)urea 1n (133.4 mg, 0.39 mmol) and CuI
(7.1 mg, 0.037 mmol) to afford 2n (81.0 mg, 80%) as a white powder.
4.1.19. 1-(4-Chlorophenyl)-1,3-dihydrobenzoimidazol-2-one (2s)
The same procedure was applied to 1-(2-bromophenyl)-1-(4-
chlorophenyl)urea 1s (96.7 mg, 0.30 mmol) and CuI (4.9 mg,
0.025 mmol) to afford 2s (47.1 mg, 57%) as a white powder. Mp:
206–208 ꢁC (hexane); IR (KBr) (
NMR (300 MHz, DMSO-d6) ( , ppm): 6.97–7.05 (m, 2H, Harom), 7.04–
7.11 (m, 2H, Harom), 7.48–7.73 (m, 4H, Harom), 11.21 (br s, 1H, NH); 13
NMR (75 MHz, DMSO-d6) ( , ppm): 108.3, 109.4, 121.1, 122.1, 127.7,
n
, cmꢂ1) 3131 (NH), 1702 (CO); 1H
Mp: 115–116 ꢁC (hexane); IR (film) (
n
, cmꢂ1) 3155 (NH), 1708 (CO);
d
1H NMR (300 MHz, CDCl3) (
d
, ppm): 00.97 (t, J¼7.4 Hz, 3H, CH3),
C
1.29–1.53 (m, 2H, CH2), 1.55–1.97 (m, 2H, CH2), 3.92 (t, J¼7.3 Hz, 2H,
CH2), 7.05 (d, J¼8.2 Hz, 1H, Harom), 7.36 (d, J¼8.2 Hz, Harom), 7.40 (s,
d
129.5 (CH), 128.5, 129.7, 131.6, 133.6, 153.2 (C); MS (EI) m/z: 246
(Mþ2,17), 245 (Mþ1, 6), 244 (M,100), 181 (30),167 (12). HRMS (EI):
calculated for C13H9Cl35N2O, 244.0403; found, 244.0401.
The same procedure was applied to 1-benzyl-1-(2-bromophen-
yl)urea 1a (20.00 g, 60.81 mmol), CuI (0.96 g, 5.17 mmol), TMEDA
(31.42 mL, 216.6 mmol) and water (720.9 mL) to provide the
corresponding benzoimidazolone 2a (12.83 g, 85%) as a white
powder.
1H, Harom), 11.13 (br s, 1H, NH); 13C NMR (75 MHz, CDCl3) (
d, ppm):
13.6 (CH3), 20.0, 30.4, 40.9 (CH2), 107.0 (q, J¼3.7 Hz), 107.6, 118.6 (q,
J¼3.8 Hz), 123.7 (q, J¼238.9 Hz, CF3), 125.6, 128.1, 132.8, 156.2 (C);
MS (EI) m/z: 259 (Mþ1, 1), 258 (M, 26), 241 (17), 216 (33), 215 (40),
202 (100), 187 (47). HRMS (EI): calculated for C12H13F3N2O,
258.0980; found, 258.0984.
4.1.15. 1-(Allyl)-1,3-dihydrobenzoimidazol-2-one (2o)
The same procedure was applied to 1-allyl-1-(2-bromophenyl)-
urea 1o (100.0 mg, 0.39 mmol) and CuI (7.2 mg, 0.037 mmol) to
afford 2o (48.3 mg, 71%) as a white powder.12 Mp: 79–80 ꢁC
Acknowledgements
This research was supported by Regional Government of Biscay/
Basque Government/University of the Basque Country (Projects
DIPE 06/10, UNESCO07/08 and GIC07/IT-349-07) and the Spanish
Ministry of Education and Science (MEC CTQ2007-64501). N.B.
thanks the Ministry of Education and Science (MEC) for a pre-
doctoral scholarship. The authors also thank S. A. Petronor for
generous donation of hexane.
(hexane); IR (film) (n
, cmꢂ1) 3143 (NH), 1696 (CO); MS (EI) m/z: 175
(Mþ1, 4), 174 (M, 100), 133 (25), 131 (13), 119 (18), 106 (22).
4.1.16. 1-(Phenyl)-1,3-dihydrobenzoimidazol-2-one (2p)
The same procedure was applied to 1-(2-bromophenyl)-1-
(phenyl)urea 1p (98.8 mg, 0.34 mmol) and Cu(OAc)2 (9.2 mg,
0.046 mmol) to afford 2p (49.2 mg, 69%) as a white powder. Mp:
187–188 ꢁC (hexane), lit.16 200–202 ꢁC (benzene); IR (film) (
n,
Supplementary data
cmꢂ1) 3143 (NH),1702 (CO); 1H NMR (300 MHz, DMSO-d6) (
6.85–7.17 (m, 2H, Harom), 7.34–7.45 (m, 2H, Harom), 7.43–7.69 (m, 5H,
arom), 11.16 (br s, 1H, NH); 13C NMR (75 MHz, DMSO-d6) (
, ppm):
d, ppm):
Experimental procedures, characterization data of all new
starting urea derivatives 1 and intermediates as well as 1H and 13
C
H
d
108.2, 109.2, 121.0, 121.9, 126.0, 127.4, 129.5 (CH), 128.5, 130.1,
134.6, 153.3 (C); MS (EI) m/z: 211 (Mþ1, 5), 210 (m, 100), 181 (37),
168 (11), 84 (10), 66 (11). HRMS (EI): calculated for C13H10N2O,
210.0793; found, 210.0792.
for all new compounds. This material is available free of charge via
Internet. Supplementary data associated with this article can be
References and notes
4.1.17. 1-Phenyl-5-fluoro-1,3-dihydrobenzoimidazol-2-one (2q)
The same procedure was applied to 1-(2-bromo-4-fluoro-
phenyl)-1-(phenyl)urea 1q (80.7 mg, 0.22 mmol) and Cu(OAc)2$
H2O(7.0 mg, 0.036 mmol) to afford 2q (34.0 mg, 57%) as a white
1. (a) Kunz, K.; Scholz, U.; Ganzer, D. Synlett 2003, 2428; (b) Ley, S. V.; Thomas,
A. W. Angew. Chem., Int. Ed. 2003, 42, 5400; (c) Beletskaya, I. P.; Cheprakov, A. V.
Coord. Chem. Rev. 2004, 248, 2337.
2. Schmidtchen, F. P.; Berger, M. Chem. Rev. 1997, 97, 1609.
powder. Mp: 211–212 ꢁC (hexane); IR (KBr) (
n
, cmꢂ1) 3414 (NH),
3. (a) Nandakumar, M. V. Tetrahedron Lett. 2004, 45, 1989; (b) Buchwald, S. L.;
Klapars, A.; Antilla, J.; Job, G. E.; Wolter, M.; Kwong, F. Y.; Nordmann, G.;
Hennessy, E. J. International Patent WO02085838, 2002; Chem. Abstr. 2002, 137,
352492; (c) Hosseinzadeh, R.; Sarrafi, Y.; Mohadjerani, M.; Mohammadpourmir,
F. Tetrahedron Lett. 2008, 49, 840.
1655 (CO); 1H NMR (300 MHz, DMSO-d6) (
d, ppm): 6.73–6.80 (m,
1H, Harom), 6.89 (d, J¼2.37 Hz, 1H, Harom), 6.90–7.01 (m, 1H, Harom),
7.33–7.50 (m, 1H, Harom), 7.51–7.62 (m, 4H, Harom), 10.57 (br s, 1H,