F. J. Moreno-Dorado et al. / Tetrahedron 59 (2003) 7743–7750
7749
CH2Cl2 was added dropwise a solution of 1.5 g (6.0–
6.5 mmol) of 70–75% mCPBA in 50 mL of CH2Cl2 at 08C.
After stirring for 1 h at 08C, the reaction mixture was diluted
with 50 mL of saturated aqueous Na2S2O3. The organic
layer was washed with saturated aqueous NaHCO3 and
brine, dried over MgSO4 and evaporated under reduced
pressure to yield 1.15 g (97%) of 26: IR (CCl4) 2966, 2943,
J¼6.9 Hz, H-3), 2.31 (dd, J¼15.3, 7.3 Hz, 1H), 2.58 (m,
1H), 3.13 (d, J¼8.1 Hz, 1H, vCCHCHOH), 4.10 (dd,
J¼8.1, 4.6 Hz, 1H, CHOH), 4.90 (br s, 1H, CHv), 5.29 (br
s, 1H, CHv); 13C NMR (100 MHz) d 14.4 (q), 18.2 (q),
18.3 (q), 21.6 (t), 26.3 (t), 31.6 (d), 34.1 (t), 34.5 (t), 35.1 (d),
59.5 (d), 76.1 (d), 90.3 (s), 94.3 (s), 112.4 (t), 151.1 (s). MS
m/z (r.i.) 236 (Mþ, 64), 218 (5), 147 (54), 137 (31), 132 (14),
120 (21), 109 (100), 108 (16), 81 (18), 71 (31), 43 (30).
HRMS calcd for C15H24O2 (Mþ) 236.1776, found
236.1779.
1
2906, 2872, 1463, 1081, 1053, 977, 903 cm21; H NMR
(600 MHz) d 0.95 (d, J¼6.9 Hz, 3H, CHMe), 0.97 (d,
J¼7.1 Hz, 3H, CHMe), 0.98 (d, J¼7.1 Hz, 3H, CHMe),
1.04 (d, J¼6.9 Hz, 3H, CHMe), 1.31 (dd, J¼13.8,
5.4 Hz, 1H, CH2CHCHMe), 1.32 (dd, J¼13.8, 5.4 Hz, 1H,
CHCH2CHMe), 1.61–1.71 (m, 2H, CH2CH2CHMe), 1.65
(qd, J¼6.9, 6.6 Hz, 1H, CHMe), 1.72 (ddd, J¼13.8, 13.8,
5.4 Hz, 1H, CHCH2CHMe), 1.82 (dddd, J¼13.2, 13.2, 7.0,
3.6 Hz, 1H, CH2CHCHMe), 1.87 (dddd, J¼13.8, 13.8, 6.6,
5.4 Hz, 1H, CH2CHCHMe), 1.98 (septet, J¼7.1 Hz, 1H,
CHMe2), 2.27 (dddd, J¼13.2, 9.8, 8.5, 8.5 Hz, 1H,
CH2CHCHMe), 2.51 (ddq, J¼9.8, 7.0, 6.9 Hz, 1H,
CHMe), 3.58 (s, 1H, CHOC); 13C NMR d 14.0 (q), 14.7
(q), 17.1 (q), 17.9 (q), 20.9 (t), 23.8 (t), 25.4 (d), 26.4 (t),
30.3 (d), 32.4 (d), 35.1 (t), 56.4 (d), 76.9 (s), 88.4 (s), 91.1
(s). MS m/z (r.i.) 236 (Mþ, 11), 218 (4), 207 (8), 203 (10),
175 (10), 147 (100), 138 (54), 123 (45), 109 (64), 43 (35).
HRMS calcd for C15H24O2 (Mþ) 236.1776, found
236.1776.
4.1.15. (1S,4R,7R,10R)-4,10,12,12-Tetramethyl-11-oxa-
tricyclo[5.3.2.01,5]dodec-5-ene (31) and (1R,4R)-1,4-
dimethyl-1,2,3,4,5,6-hexahydroazulene (32). To a stirred
solution of 200 mg (0.91 mmol) of 20 in 20 mL of acetone
was added 16 mg (0.08 mmol) of TsOH·H2O at room
temperature. After stirring for 10 min, the reaction mixture
was diluted with saturated aqueous NaHCO3 and extracted
with three 20-mL portions of CH2Cl2. The combined
organic layers were washed with brine, dried over MgSO4
and evaporated under reduced pressure. The residue was
column chromatographed (PE–PE/EA 99:1) to yield 19 mg
(10%) of 24, 83 mg (42%) of 31 and 30 mg (20%) of 32 as
an unstable oil.
Compound 31: IR (neat) 1453, 1375, 1141, 1019 cm21; 1H
NMR d 0.81 (d, J¼7.1 Hz, 3H, CHMe), 1.00 (s, 3H, Me),
1.18 (d, J¼6.8 Hz, 3H, CHMe), 1.28 (s, 3H, Me), 1.21–2.15
(m, 12H), 2.67 (m, 1H), 5.91 (dd, J¼2.5, 7.7 Hz, 1H,
CHv); 13C NMR d 18.5 (q), 19.1 (q), 22.0 (t), 30.1 (q), 30.5
(q), 32.7 (t), 32.2 (t), 35.5 (d), 38.7 (q), 40.4 (d), 42.4 (d),
75.4 (s), 86.8 (s), 121.5 (d), 149.1 (s); MS m/z (r.i.) 220 (Mþ,
67), 205 (100), 177 (32), 162 (20), 149 (20), 138 (87), 123
(40), 109 (28), 105 (22), 91 (23). HRMS calcd for C15H24O
(Mþ) 220.1827, found 220.1824.
4.1.14. (1R,5S,6R,7R,10R)-7-Isopropyl-4,10-dimethyl-
11-oxatricyclo[5.3.2.01,5]undec-3-en-6-ol (27) and
(1R,5S,6R,7R,10R)-7-isopropyl-10-methyl-4-methylene-
11-oxatricyclo-[5.3.2.01,5]undecan-6-ol (28). To a stirred
solution of 560 mg (2.37 mmol) of 26 in 100 mL of dry
Et2O was added 0.3 mL (2.85 mmol) of BF3·Et2O at 08C.
After stirring for 2 h at 08C, the reaction mixture was diluted
with 50 mL of saturated aqueous NaHCO3. The organic
layer was washed twice with saturated aqueous NaHCO3
and brine, dried over MgSO4 and evaporated under reduced
pressure. The residue was column chromatographed (PE/EA
19:1) to yield 403 mg (72%) of 27 and 145 mg (26%) of 28.
1
Compound 32: H NMR (C6D6) d 1.02 (d, J¼7.0 Hz, 3H,
CHMe), 1.11 (d, J¼6.8 Hz, 3H, CHMe), 0.9–2.9 (m, 10H),
5.8–6.1 (m, 2H, CHvCH); 13C NMR (C6D6) d 19.8 (q),
20.2 (q), 26.9 (t), 31.3 (t), 31.7 (t), 35.8 (d), 36.0 (t), 44.5 (d),
124.4 (d), 132.1 (d), 142.4 (s), 144.1 (s). Due to the
instability of diene 32, no satisfactory HRMS data have
been obtained.
Compound 27: IR (CCl4) 3578, 2961, 2877, 2840, 1709,
1466, 1400, 1377, 1075, 1047 cm21; 1H NMR (400 MHz) d
0.87 (d, J¼6.8 Hz, 3H, CHMe), 0.99 (d, J¼6.9 Hz, 3H,
CHMe), 1.00 (d, J¼6.9 Hz, 3H, CHMe), 1.15 (m, 1H), 1.43
(m, 1H), 1.44 (d, J¼4.5 Hz, 1H), 1.52 (m, 1H), 1.71–1.79
(m, 2H), 1.83 (br s, 3H, vCMe), 2.05 (septet, J¼6.9 Hz,
1H, CHMe2), 2.14 (ddt, J¼17.4, 4.7, 2.3 Hz, 1H), 2.35 (ddt,
J¼17.4, 4.0, 2.0 Hz, 1H), 3.17 (d, J¼7.4 Hz, 1H,
vCCHCHOH), 4.07 (dd, J¼7.4, 4.5 Hz, 1H, CHOH),
5.39 (br s, 1H, CH2CHv); 13C NMR (100 MHz) d 14.0 (q),
17.7 (q), 17.9 (q), 18.0 (q), 19.8 (t), 25.6 (t), 31.4 (d), 35.4
(d), 42.1 (t), 63.4 (d), 76.3 (d), 89.8 (s), 92.8 (s), 127.8 (d),
137.9 (s). MS m/z (r.i.) 236 (Mþ, 87), 218 (7), 175 (11), 147
(62), 132 (49), 121 (23), 120 (22), 109 (100), 43 (21).
HRMS calcd for C15H24O2 (Mþ) 236.1776, found
236.1779.
4.1.16. (1S,4R,5S,7R,8R,11R)-4,11,13,13-Tetramethyl-
6,12-dioxatetracyclo[6.3.2.01,5.05,7]tridecane (33). To a
stirred solution of 450 mg (2.1 mmol) of 31 in 25 mL of
CH2Cl2 was added dropwise a solution of 1.0 g (4.1–
4.3 mmol) of 70–75% mCPBA in 25 mL of CH2Cl2 at room
temperature. After stirring for 7 days, the reaction mixture
was diluted with 50 mL of saturated aqueous Na2S2O3. The
organic layer was washed with saturated aqueous NaHCO3
and brine. The combined aqueous layers were extracted
with two 25-mL portions of ether. The combined organic
layers were dried over MgSO4 and evaporated under
reduced pressure. The residue was column chromato-
1
graphed (PE/EA 49:1) to yield 415 mg (86%) of 33: H
Compound 28: IR (CCl4) 3547, 2961, 2876, 1466 1376,
1176, 1115, 1079, 1055 cm21; 1H NMR (400 MHz) d 0.93
(d, J¼6.8 Hz, 3H, CHMe), 1.00 (d, J¼6.9 Hz, 3H, CHMe),
1.04 (d, J¼6.9 Hz, 3H, CHMe), 1.25 (m, 1H), 1.37 (dt,
J¼13.1, 7.4 Hz, 1H), 1.49 (m, 2H), 1.74 (m, 2H), 1.93 (d,
J¼4.6 Hz, 1H), 1.96 (dd, J¼13.0, 7.4 Hz, 1H), 2.12 (septet,
NMR d 0.98 (d, J¼6.9 Hz, 3H, CHMe), 1.07 (d, J¼7.0 Hz,
3H, CHMe), 1.12 (s, 3H, Me), 1.45 (s, 3H, Me), 1.50–2.14
(m, 11H), 3.31 (d, J¼6.2 Hz, 1H, CHOC); 13C NMR d 15.3
(q), 16.6 (q), 20.1 (t), 26.2 (t), 26.8 (q), 29.8 (q), 30.0 (t),
36.4 (d), 36.9 (t), 38.5 (d), 38.7 (d), 58.5 (d), 66.5 (s), 73.6
(s), 85.8 (s); MS m/z (r.i.) 236 (Mþ, 6), 178 (62), 123 (100),