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7335
References
boxaldehyde has previously been reported, however, the
product was the over-reduced compound, 3-(4-
piperidinyl)methylindole.8
1. (a) Malleron, J. L.; Gueremy, C.; Mignani, S.; Peyronel,
J.-F.; Truchon, A.; Blanchard, J.-C.; Doble, A.; Laduron,
P.; Piot, O.; Zundel, J.-L.; Betschart, J.; Canard, H.;
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13. Physical and spectroscopic data for compounds: 3a, mp
190–193°C; lit.11e 151–152°C; 3b, mp 171–173°C; 1H
NMR (DMSO-d6) l 5.84 (s, 1H), 5.93 (s, 1H), 6.86–6.90
(m, 1H), 7.16–7.19 (m, 1H), 7.24 (s, 1H), 7.31–7.33 (m,
1H), 7.42–7.43 (m, 2H), 8.47–8.48 (m, 2H), 11.06 (s, 1H);
3c, mp 178–179°C; 1H NMR (DMSO-d6) l 5.84 (d,
J=4.1 Hz, 1H), 5.93 (d, J=3.8 Hz, 1H), 6.75–6.79 (m,
1H), 7.08–7.11 (m, 1H), 7.16 (d, J=2.0 Hz, 1H), 7.42 (d,
J=7.3 Hz, 2H), 7.44–7.45 (m, 1H), 8.46–8.47 (m, 2H),
1
11.01 (s, 1H); 3d, mp 265°C (dec.); H NMR (DMSO-d6)
2. Kelly, M. G.; Kang, Y. H. US 6,066,637, May 23, 2000;
l 6.06 (s, 1H), 6.11 (s, 1H), 7.42 (s, 1H), 7.44–7.46 (m,
2H), 7.52 (d, J=9.0 Hz, 1H), 7.96 (dd, J=9.0, 2.2 Hz,
1H), 8.49 (d, J=2.2 Hz, 1H), 8.50–8.52 (m, 2H), 11.72 (s,
Chem. Abstr. 2000, 132, 347587.
3. Kelly, M. G.; Kang, Y. H. WO 9,955,697 A1, November
4, 1999; Chem. Abstr. 1999, 131, 322541.
1
1H); 3e, mp 197–199°C; H NMR (DMSO-d6) l 5.99 (s,
4. Dickinson, R. P.; Dack, K. N.; Steele, J. Bioorg. Med.
1H), 6.00 (s, 1H), 7.39 (s, 1H), 7.41 (dd, J=8.5, 1.5 Hz,
1H), 7.44–7.46 (m, 2H), 7.51 (d, J=8.5 Hz, 1H), 7.98–
7.99 (m, 1H), 8.48–8.50 (m, 2H), 11.56 (s, 1H).
Chem. Lett. 1995, 5, 3017.
5. Uzan, A. V. EP 7258, January 23, 1980; Chem. Abstr.
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Org. Chem. 1983, 48, 4836; (b) Bosch, J.; Feliz, M.;
Bennasar, M.-L. Tetrahedron 1984, 40, 1419.
7. Kametani, T.; Suzuki, T.; Takahashi, K.; Ichikawa, Y.;
Fukumoto, K. J. Chem. Soc., Perkin Trans. 1 1975, 413.
8. Gray, A. P. J. Org. Chem. 1958, 23, 1453.
14. For a review on hydrosilane-mediated reduction of ben-
zylic alcohols, see: Kursanov, D. N.; Parnes, Z. N.; Loim,
N. M. Synthesis 1974, 633.
15. Physical and spectroscopic data for compounds: 4a, mp
110°C, lit.9 108–110°C; 1H NMR (DMSO-d6) l 4.05 (s,
2H), 6.91–6.94 (m, 1H), 7.03–7.07 (m, 1H), 7.22 (d,
J=2.4 Hz, 1H), 7.25–7.27 (m, 2H), 7.34 (d, J=8.2 Hz,
1H), 7.39 (d, J=7.9 Hz, 1H), 8.40–8.42 (m, 2H), 10.91 (s,
1H); 4b, mp 141–142°C, lit.1 mp 149°C; 4c, mp 131°C; 1H
NMR (DMSO-d6) l 4.03 (s, 2H), 6.77–6.81 (m, 1H), 7.11
(dd, J=10.2, 2.3 Hz, 1H), 7.21 (d, J=2.3 Hz, 1H), 7.26
(d, J=6.0 Hz, 2H), 7.38 (dd, J=8.7, 5.5 Hz, 1H), 8.40–
9. DeGraw, J. L.; Kennedy, J. G.; Skinner, W. A. J. Hete-
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10. Moldvai, I.; Gacs-Baitz, E.; Szantay, C. Recl. Trav.
Chim. Pays-Bas 1991, 110, 437.
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(b) Martinez, S. J.; Joule, J. A. J. Chem. Soc. Perkin
Trans 1, 1979, 3155; (c) Amat, M.; Hadida, S.; Sathya-
narayana, S.; Bosch, J. J. Org. Chem. 1994, 59, 10; (d)
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Am. Chem. Soc. 1959, 81, 163.
1
8.42 (m, 2H), 10.98 (s, 1H); 4d, mp 196–197°C; H NMR
(DMSO-d6) l 4.16 (s, 2H), 7.28–7.30 (m, 2H), 7.50 (s,
1H), 7.52 (d, J=9.0 Hz, 1H), 7.97 (dd, J=8.8, 2.2 Hz,
1H), 8.41–8.42 (d, J=2.0 Hz, 1H), 8.43–8.45 (m, 2H),
1
11.71 (s, 1H); 4e, mp 185–187°C; H NMR (DMSO-d6) l
4.09 (s, 2H), 7.28–7.30 (m, 2H), 7.40 (dd, J=8.5, 1.7 Hz,
1H), 7.44 (s, 1H), 7.49 (d, J=1.7 Hz, 1H), 8.00–8.01 (m,
1H), 8.42–8.44 (m, 2H), 11.53 (s, 1H).
12. Direct reductive alkylation of indoles with 4-pyridinecar-