Z. Li et al. / Tetrahedron 67 (2011) 9844e9852
9851
1379 cmꢀ1
.
1H NMR (CDCl3):
d
5.55e5.53 (m, 1H), 3.65e3.63 (m,
1242 cmꢀ1
.
1H NMR (CDCl3):
d
5.29e5.27 (m, 1H), 3.74 (s, 3H),
0.5H), 3.41e3.34 (m, 0.5H), 3.21e3.08 (m, 1H), 2.78e2.71 (m, 0.5H),
2.65e2.38 (m, 3H), 2.33e2.26 (m, 1H), 2.21e2.16 (m, 1H), 2.12e1.98
(m, 1H), 1.83e1.78 (m, 0.5H), 1.74e1.60 (m, 1H), 1.51e1.44 (m, 0.5H),
2.98e2.94 (m, 1H), 2.82e2.75 (m, 1H), 2.70e2.62 (m, 1H),
2.26e2.21 (m, 1H), 2.01e1.93 (m, 1H), 1.88 (s, 3H), 1.83e1.75 (m,
3H), 1.53e1.41 (m, 1H), 1.33e1.24 (m, 1H), 1.11e1.01 (m, 1H). 13C
1.18e1.08 (m, 1H), 1.00e0.96 (m, 3.5H). 13C NMR (CDCl3):
d
196.4,
NMR (CDCl3): d 169.7, 138.8, 127.2, 113.8, 51.0, 39.9, 35.5, 34.7, 34.3,
195.6, 139.4, 138.7, 125.0, 121.9, 95.0, 93.6, 53.1, 46.1, 38.3, 35.9, 35.5,
34.7, 33.1, 32.2, 30.8, 27.7, 23.9, 23.6, 22.2. HRMS (EI): m/z calcd for
[C12H16Cl2O]: 246.0578. Found: 246.0574.
28.5, 26.7, 20.7. HRMS (EI): m/z calcd for [C13H18O2]: 206.1307.
Found: 206.1305.
4.7.3. Hexahydronaphthalene-1-carboxylate 1c. A solution of 2c
(1.0 equiv, 0.045 mmol, 11 mg) and DBU (3.2 equiv, 0.143 mmol,
22 mg) in 1.0 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/EtOAc¼30:1), affording 1c (6 mg, 65% yield).
4.6.6. 1,1-Dichloro bicyclo[5.4.0]undec-5-en-2-one 2f. A solution of
6f (1.0 equiv, 0.13 mmol, 34 mg) in 1.0 mL mesitylene was heated
to reflux under nitrogen atmosphere for 14 h. After cooling to
room temperature, the mixture was purified by flash chroma-
tography (SiO2, petroleum ether/CH2Cl2¼5:1), affording 2f (20 mg,
59% yield, dr¼1:1). IR (neat): 2955, 2930, 2872, 1747, 1457, 1375,
IR (neat): 2959, 2929, 2872, 1719, 1457, 1436, 1252 cmꢀ1 1H NMR
.
(CDCl3):
d
6.81 (dd, J¼1.6 Hz, J¼3.2 Hz, 1H), 5.25 (d, J¼1.6 Hz, 1H),
3.74 (s, 3H), 2.94e2.86 (m, 2H), 2.30e2.24 (m, 1H), 2.22e2.21 (m,
1H), 2.04e1.95 (m, 2H), 1.86e1.71 (m, 4H), 1.12 (d, J¼7.2 Hz, 3H). 13C
1240, 1048 cmꢀ1. 1H NMR (CDCl3):
d 5.46e5.40 (m, 1H), 3.80e3.57
(m, 2H), 2.75e2.56 (m, 1H), 2.46e2.18 (m, 2H), 2.14e1.94 (m, 3H),
1.80e1.57 (m, 2.5H), 1.47e1.39 (m, 0.5H), 1.23e1.19 (m, 3H), 1.04
(d, J¼6.4 Hz, 1.5H), 0.97 (d, J¼6.4 Hz, 1.5H). 13C NMR (CDCl3):
NMR (CDCl3): d 167.7, 141.4, 138.9, 131.1, 119.9, 51.3, 38.4, 35.9, 35.8,
32.1, 29.0, 26.9, 22.0. HRMS (EI): m/z calcd for [C13H18O2]: 206.1307.
Found: 206.1303.
d
198.5, 197.9, 137.8, 137.4, 125.7, 123.9, 95.9, 94.4, 49.1, 44.9, 38.9,
37.7, 35.9, 35.0, 33.1, 32.8, 31.7, 31.5, 31.3, 31.1, 27.9, 27.7, 22.7, 22.6,
17.5. HRMS (EI): m/z calcd for [C13H18Cl2O]: 260.0735. Found:
260.0732.
4.7.4. Hexahydronaphthalene-1-carboxylate 1d. A solution of 2d
(1.0 equiv, 0.81 mmol, 200 mg) and DBU (3.0 equiv, 2.4 mmol,
0.36 mL) in 1.6 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/Et2O¼4:1), affording 1d (129 mg, 77% yield).
4.6.7. 1,1-Dichloro bicyclo[5.4.0]undec-5-en-2-one 2g. A solution of
6g (1.0 equiv, 0.123 mmol, 32 mg) in 1.0 mL toluene was heated to
reflux under nitrogen atmosphere for 14 h. After cooling to room
temperature, the solvent was removed under vacuum and the
residue was purified by flash chromatography (SiO2, petroleum
ether/CH2Cl2¼5:1), affording 2g (18 mg, 56% yield, dr¼1:1). IR
(neat): 2955, 2927, 2870, 1743, 1457, 1377, 1217, 1093 cmꢀ1. 1H NMR
IR (neat): 2927, 2854, 1718, 1691, 1436, 1258, 1222 cmꢀ1 1H NMR
.
(CDCl3):
2.80e2.69 (m, 2H), 2.17e1.67 (m, 4H), 1.65 (s, 3H), 1.59e0.96 (m,
4H). 13C NMR (CDCl3):
167.6, 135.9, 132.2, 132.1, 118.1, 51.4, 39.4,
d 6.86e6.85 (m, 1H), 3.74 (s, 3H), 2.93e2.91 (m, 1H),
d
35.4, 33.9, 30.1, 28.4, 26.9, 17.7. HRMS (EI): m/z calcd for [C13H18O2]:
206.1307. Found: 206.1310.
(CDCl3):
d
3.62 (d, J¼8.0 Hz, 0.5H), 3.50 (dd, J¼5.6 Hz, J¼10.8 Hz,
4.7.5. Hexahydronaphthalene-1-carboxylate 1e. A solution of 2e
(1.0 equiv, 0.08 mmol, 20 mg) and DBU (3.0 equiv, 0.27 mmol,
41 mg) in 2.0 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/EtOAc¼30:1), affording 1e (11 mg, 68%
yield, dr¼1:1). IR (neat): 2952, 2927, 2852, 1719, 1645, 1456, 1436,
0.5H), 3.37e3.27 (m, 1H), 2.88e2.79 (m, 0.5H), 2.73e2.60 (m, 1.5H),
2.56e2.45 (m, 1H), 2.39e2.31 (m, 0.5H), 2.29e2.15 (m, 2H),
2.07e2.01 (m, 1H), 1.80e1.74 (m, 1H), 1.70 (s, 1.5H), 1.65 (s, 1.5H),
1.54e1.32 (m, 1.5H), 1.25 (s, 1H), 1.01 (d, J¼6.4 Hz, 1.5H), 0.94 (d,
J¼6.4 Hz, 1.5H). 13C NMR (CDCl3):
d
195.8, 195.0, 132.9, 131.6, 131.3,
1252 cmꢀ1 1H NMR (CDCl3):
. d 6.89e6.87 (m, 1H), 5.31e5.29 (m,
130.4, 95.1, 93.7, 50.6, 47.4, 35.6, 34.5, 33.1, 32.6, 32.2, 31.7, 31.5, 29.7,
28.0, 27.5, 27.0, 26.0, 22.7, 22.5, 21.1, 20.9. HRMS (EI): m/z calcd for
[C13H18Cl2O]: 260.0735. Found: 260.0738.
1H), 3.74 (s, 1.5H), 3.73 (s, 1.5H), 3.25e3.17 (m, 0.5H), 3.03e2.96
(m, 0.5H), 2.86e2.81 (m, 2H), 2.27e2.22 (m, 1H), 2.15e1.95 (m,
3H), 1.82e1.67 (m, 1H), 1.62e1.58 (m, 1H), 1.33e1.25 (m, 1H), 1.15
(d, J¼7.2 Hz, 1.5H), 0.87 (d, J¼7.2 Hz, 1.5H). 13C NMR (CDCl3):
4.7. General procedure for synthesis of 3,5,6,7,8,8a-
hexahydronaphthalene-1-carboxylates 1
d 167.5, 140.4, 139.5, 136.2, 136.0, 131.9, 131.7, 113.2, 112.8, 51.3,
42.9, 40.4, 37.3, 37.2, 35.4, 34.1, 33.1, 32.2, 30.5, 28.3, 27.7, 27.5,
22.0, 17.5. HRMS (EI): m/z calcd for [C13H18O2]: 206.1307. Found:
206.1311.
A solution of the appropriate 2 (1.0 equiv) and DBU (3.3 equiv) in
MeOH or EtOH was heated to reflux under nitrogen atmosphere for
30 min. After cooling to room temperature, the solvent was re-
moved under vacuum and the residue was purified by flash chro-
matography (SiO2, petroleum ether/EtOAc¼30:1), affording 1.
4.7.6. Hexahydronaphthalene-1-carboxylate 1f. A solution of 2e
(1.0 equiv, 0.048 mmol, 12 mg) and DBU (3.2 equiv, 0.15 mmol,
24 mg) in 1.0 mL EtOH was subjected to the general procedure
(SiO2, petroleum ether/EtOAc¼30:1), affording 1f (6 mg, 57% yield,
dr¼4:7). IR (neat): 2955, 2927, 2853, 1716, 1689, 1456, 1250, 1179,
4.7.1. Hexahydronaphthalene-1-carboxylate 1a. A solution of 2a
(1.0 equiv, 0.858 mmol, 200 mg) and DBU (3.0 equiv, 2.6 mmol,
0.38 mL) in 1.7 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/Et2O¼9:1), affording 1a (96 mg, 58% yield).
IR (neat): 2930, 2855, 1720, 1689, 1436, 1255 cmꢀ1. 1H NMR (CDCl3):
1069 cmꢀ1 1H NMR (CDCl3):
. d 6.90e6.86 (m, 1H), 5.31e5.29 (m,
1H), 4.23e4.16 (m, 2H), 3.26e3.18 (m, 0.5H), 3.04e2.95 (m, 0.5H),
2.86e2.82 (m, 2H), 2.27e2.22 (m, 1H), 2.17e2.12 (m, 1H), 2.08e1.96
(m, 2H), 1.82e1.67 (m, 2H), 1.62e1.58 (m, 1H), 1.31e1.28 (m, 3H),
1.15 (d, J¼7.2 Hz, 1.1H), 0.88 (d, J¼7.2 Hz, 1.9H). 13C NMR (CDCl3):
d
6.91e6.88 (m, 1H), 5.30 (d, J¼1.2 Hz, 1H), 3.74 (s, 3H), 2.97e2.92
(m, 1H), 2.85e2.83 (m, 2H), 2.28e1.77 (m, 4H), 1.59e0.98 (m, 4H).
13C NMR (CDCl3):
167.6, 139.9, 136.2, 131.8, 113.2, 51.4, 38.0, 35.9,
d
167.1, 140.4, 139.5, 135.9, 135.6, 132.0, 113.3, 112.8, 60.1, 42.9, 40.4,
d
37.4, 37.2, 35.4, 34.1, 33.1, 32.3, 30.6, 28.3, 27.7, 27.5, 22.1, 17.4, 14.2.
34.9, 28.9, 27.6, 26.9. HRMS (EI): m/z calcd for [C12H16O2]: 192.1150.
HRMS (EI): m/z calcd for [C14H20O2]: 220.1463. Found: 220.1467.
Found: 192.1153.
4.7.7. Hexahydronaphthalene-1-carboxylate 1g. A solution of 2f
(1.0 equiv, 0.061 mmol, 16 mg) and DBU (3.2 equiv, 0.20 mmol,
30 mg) in 1.0 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/EtOAc¼30:1), affording 1g (10 mg, 77%
yield, dr¼1:1). IR (neat): 2957, 2928, 2872, 1741, 1435, 1373, 1240,
4.7.2. Hexahydronaphthalene-1-carboxylate 1b. A solution of 2b
(1.0 equiv, 0.061 mmol, 15 mg) and DBU (3.2 equiv, 0.19 mmol,
29 mg) in 1.0 mL MeOH was subjected to the general procedure
(SiO2, petroleum ether/EtOAc¼30:1), affording 1b (7 mg, 58%
yield). IR (neat): 2958, 2930, 2873, 1720, 1554, 1457, 1377, 1268,
1138, 1048 cmꢀ1 1H NMR (CDCl3):
. d 5.28e5.26 (m, 1H), 3.75 (s,