N. Sun et al. / Tetrahedron 66 (2010) 7142e7148
7147
d
2.82 (s, 3H, NeCH3), 6.56e6.68 (m, 2H, AreH), 7.13e7.16 (m, 2H,
References and notes
AreH).
1. (a) Kirk, R. E.; Othmer, D. F.; Kirk-Othmer Encyclopedia of Chemical Technology,
3rd ed.; Wiley-Interscience: New York, NY, 1978; Vol. 2, pp 309e321; (b)
Salvatore, R. N.; Yoon, C. H.; Jung, K. W. Tetrahedron 2001, 57, 7785e7811.
2. (a) Smith, M. B.; March, J. Advanced Organic Chemistry, 5th ed.; Wiley-Interscience:
New York, NY, 2001, pp 499e501; (b) Verma, M.; Singh, K. N.; Clercq, E. D. Het-
erocycles 2006, 68,11e22; (c) Li, X.; Mintz, E. A.; Bu, X. R.; Zehnder, O.; Bosshard, C.;
Gunter, P. Tetrahedron 2000, 56, 5785e5791; (d) Willson, F. G.; Wheeler, T. S. Or-
ganic Syntheses; John Wiley & Sons: New York, NY, 1941; Collect. Vol. 1; p 102.
3. (a) Onaka, M.; Ishikawa, K.; Izumi, Y. Chem. Lett.1982,11,1783e1786; (b) Onaka, M.;
Umezono, A.; Kawai, M.; Izumi, Y. J. Chem. Soc., Chem. Commun. 1985, 1202e1203.
4. For selected literature, see: (a) Niphadkar, P. S.; Joshi, P. N.; Gurav, H. R.;
Deshpande, S. S.; Bokade, V. V. Catal. Lett. 2009, 133, 175e184; (b) Naskar, S.;
Bhattacharjee, M. Tetrahedron Lett. 2007, 48, 3367e3370; (c) Ebenezer, W. J.;
Hutchings, M. G.; Jones, K.; Lamberta, D. A.; Watt, I. Tetrahedron Lett. 2007, 48,
1641e1643; (d) Vijayaraj, M.; Gopinath, C. S. Appl. Catal. A: General 2007, 320,
64e68; (e) Nishamol, K.; Rahna, K. S.; Sugunan, S. J. Mol. Catal. A: Chem. 2004,
209, 89e96; (f) Nagaraju, N.; Kuriakose, G. New J. Chem. 2003, 27, 765e768; (g)
Fujita, K.; Li, Z.; Ozeki, N.; Yamaguchi, R. Tetrahedron Lett. 2003, 44, 2687e2690;
(h) Selva, M.; Tundo, P.; Perosa, A. J. Org. Chem. 2001, 66, 677e680; (i) Sree-
kumar, K.; Mathew, T.; Mirajkar, S. P.; Sugunan, S.; Rao, B. S. Appl. Catal. A:
General 2000, 201, L1eL8.
3.3.6. 2-Chloro-N-methylbenzenamine. Yield 87%, colorless oil; GCe
MS (EI): m/z 141 [Mþ, 78%],143 (Mþ2, 26),139 (100).1H NMR (CDCl3)
d
2.90 (s, 3H, NeCH3), 4.41 (br s,1H, NeH), 6.62e6.66 (m, 2H, AreH),
7.15e7.18 (m, 1H, AreH), 7.24e7.26 (m, 1H, AreH).
3.3.7. 3-Chloro-N-methylbenzenamine. Yield 94%, colorless oil; GCe
MS (EI): m/z 141 [Mþ, 92%],143 (Mþ2, 29),139 (100).1H NMR (CDCl3)
d
2.80 (s, 3H, NeCH3), 3.94 (br s, 1H, NeH), 6.47e6.49 (m, 1H, AreH),
6.58e6.59 (m, 1H, AreH), 6.66e6.68 (m, 1H, AreH), 7.06e7.09 (m,
1H, AreH).
3.3.8. 4-Methoxy-N-methylbenzenamine. Yield 83%, yellowish oil;
GCeMS (EI): m/z 137 [Mþ, 54%], 122 (100). 1H NMR (CDCl3)
d 2.81 (s,
3H, NeCH3), 3.75 (s, 3H, OeCH3), 6.61e6.63 (m, 2H, AreH),
6.80e6.81 (m, 2H, AreH).
5. (a) Byun, E.; Hong, B.; De Castro, K. A.; Lim, M.; Rhee, H. J. Org. Chem. 2007, 72,
9815e9817; (b) Reddy, P. S.; Kanjilal, S.; Sunitha, S.; Prasad, R. B. N. Tetrahedron
Lett. 2007, 48, 8807e8810; (c) Da Silva, R. A.; Estevam, I. H. S.; Bieber, L. W.
Tetrahedron Lett. 2007, 48, 7680e7682; (d) Bhanushali, M. J.; Nandurkar, N. S.;
Bhor, M. D.; Bhanage, B. M. Tetrahedron Lett. 2007, 48, 1273e1276; (e) Nagaiah,
K.; Kumar, V. N.; Rao, R. S.; Reddy, B. V. S.; Narsaiah, A. V.; Yadav, J. S. Synth.
Commun. 2006, 36, 3345e3352; (f) Cho, B. T.; Kang, S. K. Tetrahedron 2005, 61,
5725e5734 and references cited therein.
3.3.9. 4-Fluoro-N-methylbenzenamine. Yield 87%, colorless oil; GCe
MS (EI): m/z 125 [Mþ, 89%], 124 (100). 1H NMR (CDCl3)
d 2.81 (s, 3H,
NeCH3), 3.66 (br s, 1H, NeH), 6.54e6.57 (m, 2H, AreH), 6.88e6.92
(m, 2H, AreH).
6. (a) Padmanabhan, S.; Reddy, N. L.; Durant, G. J. Synth. Commun.1997, 27, 691e699;
(b) Roberts, R. M.; Vogt, P. J. Organic Syntheses; John Wiley & Sons: New York, NY,
1963; Collect. Vol. 4; p 420.
7. Barton, D. H. R.; Ozbalik, N.; Ramesh, M. Tetrahedron Lett. 1988, 29, 857e860.
8. Takebayashi, Y.; Morita, Y.; Sakai, H.; Abe, M.; Yoda, S.; Furuya, T.; Sugeta, T.;
Otake, K. Chem. Commun. 2005, 3965e3967.
3.3.10. N-Methyl-4-(trifluoromethyl)benzenamine. Yield 93%, color-
less oil; GCeMS (EI): m/z 175 [Mþ, 70%], 174 (100). 1H NMR (CDCl3)
d
2.87 (s, 3H, NeCH3), 4.36 (br s, 1H, NeH), 6.12e6.63 (m, 2H,
AreH), 7.41e7.43 (m, 2H, AreH).
9. Yebeutchou, R. M.; Dalcanale, E. J. Am. Chem. Soc. 2009, 131, 2452e2453.
10. Iranpoor, N.; Firouzabadi, H.; Nowrouzi, N.; Khalili, D. Tetrahedron 2009, 65,
3893e3899.
11. Gonzalez, I.; Mosquera, J.; Guerrero, C.; Rodriguez, R.; Cruces, J. Org. Lett. 2009,
11, 1677e1680.
3.3.11. Ethyl 4-(methylamino)benzoate. Yield 86%, white solid, mp
63e65 ꢀC (lit.14 mp 65e67 ꢀC); GCeMS (EI): m/z 179 [Mþ, 70%],
134 (100). 1H NMR (CDCl3)
d
1.37 (t, J¼7.0 Hz, 3H, eCH2CH3), 2.88
(s, 3H, NeCH3), 4.19 (br s, 1H, NeH), 4.32 (q, J¼7.0 Hz, 2H,
12. Chiappe, C.; Piccioli, P.; Pieraccini, D. Green Chem. 2006, 8, 277e281.
13. For examples of protection and deprotection with sulfonyl groups (tosyl, nosyl),
see: (a) Cardullo, F.; Donati, D.; Fusillo, V.; Merlo, G.; Paio, A.; Salaris, M.; Sol-
inas, A.; Taddei, M. J. Comb. Chem. 2006, 8, 834e840; (b) Pera, A. L.; Leggio, A.;
Liguori, A. Tetrahedron 2006, 62, 6100e6106; (c) Li, B. F.; Yuan, K.; Dai, L. X.;
Hou, X. L. Synlett 2005, 535e537; (d) Sabitha, G.; Reddy, B. V. S.; Abraham, S.;
Yadav, J. S. Tetrahedron Lett. 1999, 40, 1569e1570; For examples of protection
and deprotection with alkoxycarbonyl groups (Boc, CBz), see: (e) Suarez-Cas-
tillo, O. R.; Montiel-Ortega, L. A.; Melendez-Rodriguez, M.; Sanchez-Zavala, M.
Tetrahedron Lett. 2007, 48, 17e20; (f) Behloul, C.; Guijarro, D.; Yus, M. Tetrahe-
dron 2005, 61, 9319e9324; (g) Strazzolini, P.; Misuri, N.; Polese, P. Tetrahedron
Lett. 2005, 46, 2075e2078; For examples of protection and deprotection with
acyl groups, see: (h) Behloul, C.; Guijarro, D.; Yus, M. Synthesis 2006, 2,
309e314; (i) Luh, T.-Y.; Fung, S. H. Synth. Commun. 1979, 9, 757e763; (j) Ka-
kimoto, S.; Tone, I. J. Med. Chem. 1965, 8, 867e868; For examples of protection
and deprotection with formyl group, see: (k) Ge, Y.; Hu, L. Tetrahedron Lett.
2007, 48, 4585e4588; (l) Blankenship, C.; Cremer, S. E. J. Organomet. Chem.
1989, 371, 19e30.
eCH2CH3), 6.54e6.56 (m, 2H, AreH), 7.87e7.90 (m, 2H, AreH).
3.3.12. 4-(Methylamino)benzonitrile. Yield 93%, white solid, mp
90e92 ꢀC (lit.13j mp 86 ꢀC); GCeMS (EI): m/z 132 [Mþ, 76%], 131
(100). 1H NMR (CDCl3)
d 2.88 (s, 3H, NeCH3), 4.46 (br s, 1H, NeH),
6.56e6.58 (m, 2H, AreH), 7.43e7.45 (m, 2H, AreH).
3.3.13. N-Methyl-4-nitrobenzenamine. Yield 76%, yellow solid, mp
150e152 ꢀC (lit.13b mp 149e151 ꢀC); GCeMS (EI): m/z 152 [Mþ,
100%]. 1H NMR (DMSO-d6)
d 2.80 (s, 3H, NeCH3), 6.60e6.61 (m, 2H,
AreH), 7.30 (br s, 1H, NeH), 8.00e8.02 (m, 2H, AreH).
3.4. Procedure for recovering the catalyst MCM-41-SO3H
14. Sekiya, M.; Ito, K. Chem. Pharm. Bull. 1966, 14, 1007e1009.
15. (a) Kadin, S. B. J. Org. Chem. 1973, 38, 1348e1350; (b) Sekiya, M.; Ito, K. Chem.
Pharm. Bull. 1967, 15, 1339e1342.
16. (a) Barluenga, J.; Bayon, A. M.; Campos, P.; Asensio, G.; Gonzalez-Nunez, E.;
Molina, Y. J. Chem. Soc., Perkin Trans. 11988, 1631e1636; (b) Barluenga, J.; Baybn,
A. M.; Asensio, G. J. Chem. Soc., Chem. Commun. 1983, 1109e1110.
17. Katritzky, A. R.; Rachwal, S.; Rachwal, B. J. Chem. Soc., PerkinTrans.11987, 805e809.
18. Katritzky, A. R.; Drewniak, M.; Aurrecoechea, J. M. J. Chem. Soc., Perkin Trans. 1
1987, 2539e2541.
After the reaction of aniline and triethyl orthoformate was
complete, the reaction mixture was cooled to room temperature.
The catalyst was filtered off and successively washed with THF
(5 mLꢁ3) and ethanol (5 mLꢁ3), then dried at 100 ꢀC for 2 h. The
recovered MCM-41-SO3H catalyst was then reused directly in the
next reaction.
19. Ha, H.-J.; Ahn, Y.-G. Synth. Commun. 1997, 27, 1543e1546.
20. Crochet, R. A., Jr.; Blanton, C. D., Jr. Synthesis 1974, 55e56.
21. Zhang, J.; Chang, H.-M.; Kane, R. R. Synlett 2001, 643e645.
Acknowledgements
22. (a) Zakyzewska, A.; Kolehmainen, E.; Osmialowski, B.; Gawinecki, R. J. Fluorine
Chem. 2001, 111, 1e10; (b) Coppola, G. M.; Schuster, H. F. J. Heterocycl. Chem.
1989, 26, 957e964; (c) Krishnamurthy, S. Tetrahedron Lett. 1982, 23, 3315e3318.
23. Blackburn, C.; LaMarche, M. J.; Brown, J.; Che, J. L.; Cullis, C. A.; Lai, S.; Maguire, M.;
Marsilje, T.; Geddes, B.; Govek, E.; Kadambi, V.; Doherty, C.; Dayton, B.; Brodjian, S.;
Marsh, K. C.; Collins, C. A.; Kym, P. R. Bioorg. Med. Chem. Lett. 2006, 16, 2621e2627.
24. The preparation of N-methyl aniline via ethyl N-phenylformimidate starting
from unsubstituted aniline was not described in Blanton and co-workers’ re-
search in the Ref. 20.
The authors gratefully acknowledge the financial support of
the National Natural Science Foundation of China (No. 20772111)
and the Natural Science Foundation of Zhejiang Province
(Y407193).
25. The reaction between aniline and triethyl orthoformate under the catalysis of
acids have been investigated by Roberts and co-workers, and the preparation
version of ethyl N-phenylformimdate have been reported inOrganic Syntheses;
John Wiley & Sons: New York, NY, 1963; Collect. Vol. 4; p 464; See also: (a)
Roberts, R. M. J. Am. Chem. Soc. 1949, 71, 3848e3849; (b) Roberts, R. M. J. Am.
Supplementary data
Supplementary data associated with this article can be found in