2378
G. Dessole et al.
LETTER
(5) (a) Vachal, P.; Jacobsen, E. N. J. Am. Chem. Soc. 2002, 124,
10012. (b) Vachal, P.; Jacobsen, E. N. Org. Lett. 2000, 2,
867. (c) Sigman, M. S.; Vachal, P.; Jacobsen, E. N. Angew.
Chem. Int. Ed. 2000, 39, 1279.
(6) Okino, T.; Nakamura, S.; Furukawa, T.; Takemoto, Y. Org.
Lett. 2004, 6, 625.
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1301. (b) McDougal, N. T.; Schaus, S. E. J. Am. Chem. Soc.
2003, 125, 12094.
(8) Mase, N.; Tanaka, F.; Barbas, C. F. III Angew. Chem. Int.
Ed. 2004, 43, 2420.
(9) List, B.; Pojarliev, P.; Martin, H. J. Org. Lett. 2001, 3, 2423.
(10) Andrey, O.; Alexakis, A.; Bernardinelli, G. Org. Lett. 2003,
5, 2559.
(11) Mase, N.; Thayumanavan, R.; Tanaka, F.; Barbas, C. F. III
Org. Lett. 2004, 6, 2527.
CDCl3): d = 1.05 (t, 3J = 7.1 Hz, 6 H, 2 × CH3CH2), 3.24 (c,
3J = 7.2 Hz, 4 H, 2 × CH3CH2), 4.71 (dd, 3J = 8.8 Hz,
3J = 7.5 Hz, 1 H, NO2CH2CH), 4.78–4.93 (m, 2 H,
NO2CH2), 6.53 (d, 3J = 8.7 Hz, 2 H, Ph), 6.97 (d, 3J = 8.7 Hz,
2 H, Ph), 7.08–7.40 (m, 5 H, Ph). 13C NMR (400 MHz,
CDCl3): d = 12.48 (2 × CH3CH2), 44.25 (NO2CH2CH),
48.21 (CH2NCH2), 79.66 (NO2CH2), 111.85 (CPh), 125.40
(CqPh), 127.26, 127.50, 127.57, 140.03, 128.55, 128.86, (5 ×
CPh) 139.97, 147.01 (2 × CqPh). MS (70 eV): m/z (%) = 298
[M+], 284 (17), 283 (86), 252 (50), 238 (100), 237 (19), 236
(56), 208 (28). HRMS: m/z calcd for C18H22N2O2: 298.1681;
found: 298.1684.
Analytical data of compound 18b: IR (CCl4): 3061, 2860,
1555, 1468, 1426, 1377 cm–1. 1H NMR (400 MHz, CDCl3):
d = 0.83 (t, J = 7.1 Hz, 3 H, CH2CH3), 1.12–1.36 (m, 6 H, 3
× CH2), 1.68–1.92 (m, 2 H, NO2CH2CHCH2), 3.76 (s, 3 H,
NCH3), 3.70–3.81 (m, 1 H, NO2CH2CH), 4.61 (dd, 2J = 11.9
Hz, 3J = 7.8 Hz, 1 H, NO2CHH), 4.66 (dd, 2J = 11.9 Hz,
3J = 7.4 Hz, 1 H, NO2CHH), 6.89 (s, 1 H, CH3NCH), 7.13 (t,
3J = 7.8 Hz, 1 H, Ph), 7.25 (t, 3J = 7.8 Hz, 1 H, Ph), 7.31 (d,
(12) Okino, T.; Hoashi, Y.; Takemoto, Y. J. Am. Chem. Soc.
2003, 125, 12672.
(13) For a recent review on catalytic stereoselective Friedel–
Crafts alkylation reactions, see: Bandini, M.; Melloni, A.;
Umani-Ronchi, A. Angew. Chem. Int. Ed. 2004, 43, 550.
(14) (a) Olah, G. A.; Krishnamurty, R.; Prakash, G. K. S.
Friedel–Crafts Alkylation in Comprehensive Organic
Synthesis, 1st ed, Vol III; Trost, B. M.; Flemming, I., Eds.;
Pergamon Press: Oxford, 1991, Chap. 1.8, 293. (b)Roberts,
R. M.; Khalaf, A. A. Friedel–Crafts Alkylation Chemistry;
Marcel Dekker: New York, 1984. (c) Friedel–Crafts
Chemistry; Olah, G. A., Ed.; Wiley: New York, 1973.
(15) Harrington, P. E.; Kerr, M. A. Synlett 1996, 1047.
(16) Komoto, I.; Kobayashi, S. Org. Lett. 2002, 4, 1115.
(17) Alam, M. M.; Varala, R.; Adapa, S. R. Tetrahedron Lett.
2003, 44, 5115.
(18) Schreiner, P. R.; Wittkopp, A. Org. Lett. 2002, 4, 217.
(19) (a) Schreiner, P. R. Chem. Soc. Rev. 2003, 32, 289.
(b) Pihko, P. M. Angew. Chem. Int. Ed. 2004, 43, 2062.
(c) Wilcox, C. S.; Kim, E.-I.; Romano, D.; Kuo, L. H.; Burt,
A. L.; Curran, D. P. Tetrahedron 1995, 51, 621.
(20) General Experimental Procedure. In a Schlenk tube, a
mixture of nitroolefin (a or b, 0.10 mmol), nitrogen-
containing aromatic or heteroaromatic compound (1–6, 13–
15, 0.15 mmol) and catalyst (I and II, 0.01 mmol) in toluene
(1 mL) or without solvent, was vigorously stirred at ambient
temperature for the appropriate time (Table 1 or Table 2).
After completion of the reaction as indicated by 1H NMR,
the reaction mixture was diluted with H2O and extracted
with Et2O. The organic phases were combined, dried over
Na2SO4 and concentrated under reduced pressure, and the
crude mixture was purified by column chromatography. All
the new compounds gave satisfactory analytical and spectral
data. Typical data for representative compounds:
Analytical data of compound 10a: IR (CCl4): 3047, 2893,
1614, 1552, 1376, 1277, 895 cm–1. 1H NMR (300 MHz,
3J = 8.2 Hz, 1 H, Ph), 7.61 (d, 3J = 8.2 Hz, 1 H, Ph). 13
C
NMR (400 MHz, CDCl3): d = 13.99 (CH2CH3), 22.43,
26.88, 31.61, 32.49 (4 × CH2), 32.77 (NCH3), 36.29
(NO2CH2CH), 80.72 (NO2CH2), 109.56 (CPh), 112.54 (CqPh),
118.83, 119.20, 121.92 (3 × CPh), 126.55 (CH3NCHC),
126.64, 137.23 (2 × CqPh). MS (70 eV): m/z (%) = 274 [M+],
228 (17), 214 (42), 171 (34), 158 (21), 157 (100), 156 (16).
HRMS: m/z calcd for C16H22N2O2: 274.1681; found:
274.1687.
(21) Bordwell, F. G.; Algrim, D. J.; Harrelson, J. A. Jr. J. Am.
Chem. Soc. 1988, 110, 5903.
(22) Scheerder, J.; Engbersen, J. F. J.; Casnati, A.; Ungaro, R.;
Reinhoudt, D. N. J. Org. Chem. 1995, 60, 6448.
(23) Cave, G. W. V.; Raston, C. L.; Scott, J. L. Chem. Commun.
2001, 2159; and references therein.
(24) Noland, W. E.; Lange, R. F. J. Am. Chem. Soc. 1959, 81,
1203.
(25) Kleeman, A.; Engel, J.; Kutscher, B.; Reichert, D.
Pharmaceutical Substances, 4th ed.; Thieme: New York,
2001.
(26) (a) Snyder, H. R.; Katz, L. J. Am. Chem. Soc. 1947, 69,
3140. (b) Noland, W. E.; Harmatman, P. J. J. Am. Chem.
Soc. 1954, 76, 3227.
(27) (a) Bandini, M.; Melchiorre, P.; Melloni, A.; Umani-Ronchi,
A. Synthesis 2002, 1110. (b) Bandini, M.; Cozzi, P. G.;
Giacomini, M.; Melchiorre, P.; Selva, S.; Umani-Ronchi, A.
J. Org. Chem. 2002, 67, 3700.
(28) (a) Hagen, T. G.; Koehler, K. F.; Codding, P. W.; Skolnick,
P.; Cook, J. M. J. Med. Chem. 1990, 33, 2343. (b) Rocca,
P.; Marsais, F.; Godard, A.; Queguiner, G. Tetrahedron
1993, 46, 3325. (c) Mérour, J.-Y.; Mérour, A. Synthesis
1994, 767.
Synlett 2004, No. 13, 2374–2378 © Thieme Stuttgart · New York