4812
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11. Polo, E.; Bellabarba, R. M.; Prini, G.; Traverso, O.; Green, M. J. Organomet. Chem.
HO
1999, 577, 211–218].
12. Wille, U.; Henger, G.; Jargstorff, C. J. Org. Chem. 2008, 73, 1413–1421.
13. Sigmund, D.; Schiesser, C. H.; Wille, U. Synthesis 2005, 1437–1444.
14. Dreessen, T.; Jargstorff, C.; Lietzau, L.; Plath, C.; Stademann, A.; Wille, U.
Molecules 2004, 9, 480–497.
15. Jargstorff, C.; Wille, U. Eur. J. Org. Chem. 2003, 3173–3178.
16. Wille, U. J. Am. Chem. Soc. 2002, 124, 14–15.
11
+ H+
H2O
17. Meier, H. Adv. Strain Org. Chem. 1991, 1, 215–272.
18. Prelog, V.; Schenker, K.; Günthardt, H. Helv. Chim. Acta 1952, 35, 1598–1615.
19. Cram, D. J.; Allinger, N. L. J. Am. Chem. Soc. 1956, 78, 2518–2524.
20. Cyclodecane-1,2-dione bishydrazone: 1H NMR (CDCl3): (E,E)-isomer (87%) d 5.30
+
(br s, 4H, NH2), 2.53 (m, 4H,
(m, 4H, CH2); (E,Z)-isomer (13%) d 5.55 (br s, 2H, NH2), 5.30 (br s, 2H, NH2), 2.67
(m, 4H,
-CH2), 1.67 (m, 4H, CH2), 1.32 (m, 4H, CH2), 1.16 (m, 4H, CH2); 13C
a-CH2), 1.67 (m, 4H, CH2), 1.32 (m, 4H, CH2), 1.16
+
a
NMR (CDCl3): (E,E)-isomer d 152.6 (CN), 25.5, 24.3, 23.5, 20.9; (E,Z)-isomer d
164.5, 151.5 (CN), 27.2, 25.8, 25.4, 24.6, 24.2, 23.6, 22.7, 21.1.
21. Mijs, W. J.; de Vries, K. S.; Westra, J. G. Rec. Trav. Chim. Pays-Bas 1968, 87, 580–
584.
12
1k
H+
H+
22. The ratio 4/40 amounts to about 50:50 in CDCl3 and to 78: 22 in CD3OD.
Compound 4: 1H NMR (CD3OD): d 4.90 (br s,1H, OH), 3.83 (m, 1H, 6-H), 2.76
3
(d,d,d, 2J = 15.7 Hz, 3J = 9.2 Hz, J0 = 3.7 Hz, 2H, 2-H, 10-H), 2.40 (d,d,d,
3
2J = 15.7 Hz, 3J = 8.3 Hz, J0 = 3.9 Hz, 2H, 2-H, 10-H), 2.10–1.45 (m, 12H,
(H+)
3,4,5,7,8,9-H); 13C NMR (CD3OD): d 217.5 (C-1), 69.9 (C-6), 42.8 (C-2, C-10),
34.5, 24.3, 23.9 (C-3,4,5, 7,8,9). Compound 40: 1H NMR (CD3OD): d 4.90 (br s,
1H, OH), 4.07 (m, 1H, 6-H), 2.10–1.45 (m, 16H, 2,3,4, 5,7,8,9,10-H); 13C NMR
1m (50%)
1l (25%)
1h (25%)
(CD3OD):
d 103.5 (C-1), 76.6 (C-6), 41.7 (C-2, C-10), 34.6, 24.3, 23.9 (C-
3,4,5,7,8,9).
23. Compound 5: Mp 173–174 °C. 1H NMR (CD3SOCD3): d 9.01 (s, 1H, NH), 6.20 (br
s, 2H, NH2), 4.21 (m, 1H, 6-H), 3.61 (br s, 1H, OH), 2.43–2.07 (m, 4H, 2,10-H),
1.84–1.18 (m,12H, 3,4,5,7,8,9-H); 13C NMR (CD3SOCD3): d 157.3 (CO), 151.1 (C-
1), 68.5 (C-6), 33.8, 32.2, 31.6, 29.3, 23.6, 22.1, 22.1, 19.8 (C-2,3,4,5,7,8,9,10).
24. Compound 6: Mp 101–103 °C. 1H NMR (CDCl3): d 3.91 (m, 1H, 8-H), 3.20 (m,
3H), 3.05 (m, 1H), 1.95 (m, 1H), 1.89 (m, 2H), 1.63 (m, 2H), 1.48 (m, 1H), 1.38
(m, 1H), 1.33 (m, 1H), 1.15 (m, 1H), 1.02 (m, 1H) [CH2 groups], 1.48 (br s, 1H,
OH). Broadening of the signals indicates that the ring dynamics are becoming
slow at room temperature in terms of the NMR time scale; 13C NMR (CDCl3): d
160.1, 159.5 (C-3a, 11a), 69.8 (C-8), 33.7, 28.3, 27.2, 27.0, 26.1, 24.9, 19.5 (C-
4,5,6,7,9,10,11).
Scheme 5. Dehydration of the bicyclic alcohol 11.
alcohol 11 with p-toluenesulfonic acid. It turned out that the re-
ported product 1k was not formed at all. We got a 2:1:1-mixture
of 1m, 1‘, and 1h in a quantitative process (Scheme 5).
The 13C NMR data permit the unambiguous differentiation be-
tween the obtained hexahydroazulenes by symmetry, multiplicity,
and chemical shift criteria (Table 1).
A preparative GC separation of the two mixtures 1c/1k/1‘ and
1h/1‘/1m seems to be easily feasible (Fig. 1); however, both mix-
tures can be directly transformed on Pd/charcoal to azulene (12).
25. Hutchins, R. O.; Hutchins, M. G.; Milewski, C. A. J. Chem. Soc. 1972, 37, 4190–
4192.
26. Compound 7: Mp 66 °C. 1H NMR (CDCl3): d 5.40 (m, 2H, 7,8-H), 3.21 (m, 1H),
3.01 (m, 2H), 2.70 (m, 1H), 2.25 (m, 2H), 2.0–1.7 (m, 6H) [CH2 groups]; 13C NMR
(CDCl3): d 160.7, 159.8 (C-3a,11a), 130.7, 129.0 (C-7,8), 31.3, 26.8, 25.2, 24.7,
23.8, 23.5 (C-4,5,6,9,10,11). 77Se NMR (CDCl3): d 203.5.
References and notes
27. See: Dale, J.; Ekeland, D.; Schaug, J. Chem. Commun. 1968, 1477–1479.
28. Compound 3: Colorless oil, bp12 110 °C; 1H NMR (CDCl3): d 5.36 (m, 2H, 1,2-H),
2.28 (m, 4H, 3,10-H), 2.19 (m, 4H, 5,8-H), 1.57 (m, 4H, 4,9-H); 13C NMR (CDCl3):
d 130.3 (C-1,2), 82.1 (C-6,7), 25.3, 23.9 (C-3,4,9,10), 18.1 (C-5,8).
29. House, H. O.; Nomura, G. S.; Van Derveer, D.; Wissinger, J. E. J. Org. Chem. 1986,
51, 2408–2416, and references therein.
1. Stanley, S. W.; Heyn, A. S. J. Am. Chem. Soc. 1975, 97, 3852–3854.
2. Boyer, F.-D.; Hanna, I. J. Org. Chem. 2005, 70, 1077–1080.
3. Boyer, F.-D.; Hanna, I. Eur. J. Org. Chem. 2006, 471–482.
4. Japenga, J.; Klumpp, G. W.; Kool, M. Rec. Trav. Chim. Pays-Bas 1978, 97, 7–9.
5. Gleiter, R.; Steuerle, U. Chem. Ber. 1989, 122, 2193–2204.
6. Dane, L. M.; De Haan, J. W.; Klosterziel, H. Tetrahedron Lett. 1970, 11, 2755–
2758.
7. Jost, R.; Chaquin, P.; Kossanyi, J. Tetrahedron Lett. 1980, 21, 465–466.
8. Vogt, T.; Winsel, H.; De Meijere, A. Synlett 2002, 1362–1364.
9. Dauphin, G.; David, L.; Kergomard, A.; Veschambre, H. Bull. Soc. Chim. Fr. 1970,
3162–3163.
30. Column chromatography (SiO2, pentane) enables a simple separation of the
mixture of 9 (35%, Rf = 0.90) and 2 (65%, Rf = 0.50). 9: 1H NMR (CDCl3): d = 5.68
3
3
3
(ddt, Jtrans = 17.0 Hz, Jcis = 10.3 Hz, J0 = 6.7 Hz, 1H, 9-H), 4.97 (m, 1H, 3-H),
4.87 (m, 1H, 10-H), 4.81 (m, 1H, 10-H), 4.52 (m, 2H, 1-H), 2.00–1.85 (m, 4H,
4,8-H), 1.37–1.20 (m, 6H, 5,6,7-H). 13C NMR (CDCl3): d = 208.6 (C-2), 138.9 (C-
9), 114.1 (C-10), 89.9 (C-3), 74.4 (C-1), 33.6 (C-8), 28.9, 28.7, 28.5, 28.1 (C-
4,5,6,7).
10. Kossanyi, J.; Jost, P.; Furth, B.; Deccord, G.; Chaquin, P. J. Chem. Res. (M) 1980,
4601–4624.
31. See for example: Snider, B. B.; Killinger, T. A. J. Org. Chem. 1978, 43, 2161–2164.
32. Anderson, A. G.; Nelson, J. A. J. Am. Chem. Soc. 1951, 73, 232–235.