2626
A. T. Khan et al. / Tetrahedron Letters 53 (2012) 2622–2626
8. Tarnavsky, S. S.; Dubinina, G. G.; Golovach, S. M.; Yarmoluk, S. M. Biopolym. Cell
2003, 19, 548.
17. Typical procedure for dihydro-2-oxopyrroles 5a: Into a 25 mL of round-bottomed
flask was taken DMAD (0.142 g, 1.0 mmol) in methanol (3 mL). Then, aniline
(0.093 g, 1 mmol) was added into it. The reaction mixture was stirred for
10 min. After that aniline (0.093 g, 1 mmol), formaldehyde (1.5 mmol) and
iodine (10 mol %) were added successively. Then the reaction mixture was kept
for stirring at room temperature until the reaction was complete, which was
monitored by TLC. The solid precipitate appeared at the end of the reaction,
which was filtered through a Büchner funnel. The product was washed with
1 mL of ethanol to remove unreacted starting materials. The pure product was
obtained after recrystallization from ethanol.
9. (a) Wrobel, M. N.; Margaretha, P. Chem. Commun. 1998, 541; (b) Metten, B.;
Kostermans, M.; Van Baelen, G.; Smet, M.; Dehaen, W. Tetrahedron 2006, 62,
6018; (c) Albrecht, D.; Basler, B.; Bach, T. J. Org. Chem. 2008, 73, 2345.
10. (a) Gao, Y.; Shirai, M.; Sato, F. Tetrahedron Lett. 1997, 38, 6849; (b) Palacios, F.;
Aparicio, D.; de los Santos, J. M.; Vicario, J. Tetrahedron 1961, 2001, 57; (c)
Dönnecke, D.; Imhof, W. Tetrahedron 2003, 59, 8499; (d) Palacios, F.; Vicario, J.;
Aparicio, D. Eur. J. Org. Chem. 2006, 2843; (e) Demir, A. S.; Emrullahoglu, M.;
Ardahan, G. Tetrahedron 2007, 63, 461; (f) Yavari, I.; Mokhtarporyani-Sanandaj,
A.; Moradi, L.; Mirzaei, A. Tetrahedron 2008, 64, 5221.
11. Zhu, Q.; Jiang, H.; Li, J.; Liu, S.; Xia, C.; Zhang, M. J. Comb. Chem. 2009, 11, 685.
12. (a) Zhu, J.; Bienayme, H. Multicomponent Reactions, 1st ed.; Wiley-VCH:
Weinheim, Germany, 2005; (b) Tempest, P. A. Curr. Opin. Drug Discov. 2005,
8, 776; (c) Dömling, A. Chem. Rev. 2006, 106, 17; (d) Ramón, D. J.; Yus, M.
Angew. Chem. 2005, 117, 1628; (e) Dömling, A.; Ugi, I. Angew. Chem., Int. Ed.
2000, 39, 3168.
Methyl 2,5-dihydro-5-oxo-1-phenyl-4-(phenylamino)-1H-pyrrole-3-carboxylate
(5a): White solid: mp 155–156 °C; 1H NMR (400 MHz, CDCl3): d 3.73 (s, 3H),
4.54 (s, 2H), 7.14 (d, J = 8.4 Hz,2H), 7.19 (t, J = 7.6 Hz, 2H), 7.32 (t, J = 7.6 Hz,
2H), 7.39 (t, J = 7.6 Hz, 2H), 7.78 (d, J = 8.4 Hz, 2H), 8.01 (s, 1H); 13C NMR
(100 MHz, CDCl3): d 48.36, 51.39, 103.03, 119.30, 122.86, 124.71, 125.16,
128.43, 129.24, 138.78, 142.98, 163.91, 164.85; IR (KBr, cmÀ1): 3269, 1692,
1646; Anal Calcd. C18H16N2O3 (308.33): requires C, 70.12; H, 5.23; N, 9.09.
Found: C, 70.10; H, 5.20; N,9.01.
Methyl 1-(4-bromophenyl)-4-(cyclohexylamino)-5-oxo-2,5-dihydro-1H-pyrrole-
3-carboxylate (5o): Yellow solid: mp 123–124 °C; 1H NMR (400 MHz, CDCl3):
d 1.15–1.27 (m, 3H), 1.37–1.46 (m, 3H), 1.61–1.68 (m, 1H), 1.73–1.77 (m, 2H),
1.99–2.02 (m, 2H), 3.79 (s, 3H), 4.37 (s, 2H), 4.57 (s, 1H), 7.49 (d, J = 8.8 Hz, 2H),
7.67 (d, J = 8.8 Hz, 2H); 13C NMR (100 MHz, CDCl3): d 24.81, 25.62, 34.89,
47.95, 51.14, 95.92, 117.89, 120.73, 132.17, 138.02, 164.51, 165.62; IR (KBr,
cm-1): 3309, 1700, 1631; Anal Calcd. C18H21BrN2O3 (392.07): requires C, 54.97;
H, 5.38; N, 7.12. Found: C, 54.88; H, 5.28; N, 7.03.
13. (a) Trost, B. M. Science 1991, 254, 1471; (b) Trost, B. M. Angew. Chem., Int. Ed.
1995, 34, 259; (c) Wender, P. A.; Handy, S. T.; Wright, D. L. Chem. Ind. 1997, 765.
14. (a) Khan, A. T.; Khan, M. M. Tetrahedron Lett. 2011, 52, 3455; (b) Khan, A. T.;
Khan, M. M.; Bannuru, K. K. R. Tetrahedron 2010, 66, 7762; (c) Khan, A. T.; Lal,
M.; Khan, M. M. Tetrahedron Lett. 2010, 51, 4419.
15. (a) Togo, H.; Iida, H. Synlett 2006, 2159; (b) Jareb, M.; Vrazic, D.; Zupan, M.
Tetrahedron 2010, 67, 1355.
16. (a) Wang, X. S.; Li, Q.; Wu, J. R.; Li, Y. L.; Yao, C. S.; Tu, S. J. Synthesis 2008, 1902;
(b) Phukan, P. J. Org. Chem. 2004, 69, 4005; (c) Phukan, P.; Kataki, D.;
Chakraborty, P. Tetrahedron Lett. 2006, 47, 5523; (d) Kidwai, M.; Mothsra, P.;
Bansal, V.; Somvanshi, R. K.; Ethayathullah, A. S.; Dey, S.; Singh, T. P. J. Mol.
Catal. A. Chem. 2007, 265, 177; (e) Lin, C.; Lai, P. T.; Liao, S. K. S.; Hung, W. T.;
Yang, W. B.; Fang, J. M. J. Org. Chem. 2008, 73, 3848; (f) Kumar, N.; Khan, S. I.;
Sharma, M.; Atheaya, H.; Rawat, D. S. Bioorg. Med. Chem. Lett. 2009, 19, 1675;
(g) Wang, X. S.; Li, Q.; Wu, J. R.; Tu, S. J. J. Comb. Chem. 2009, 11, 433; (h) Nath, J.;
Patel, B. K.; Jamir, L.; Sinha, U. B.; Satyanarayana, K. V. V. V. Green Chem. 2009,
11, 1503.
18. Complete crystallographic data of 5o for the structural analysis has been
deposited with the Cambridge Crystallographic Data Centre, CCDC No. 856176.
Copies of this information may be obtained free of charge from the Director,
Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ,
UK, (fax: +44-1223-336033, e-mail: deposit@ccdc.cam.ac.uk or via:
19. Khan, A. T.; Khan, M. M.; Das, D. K.; Lal, M. J. Heterocycl. Chem. (in press).