4
MASNYK ET AL.
120.6, 51.8, 51.0, 46.6, 45.1, 38.3, 37.1, 34.9, 34.6, 27.5,
25.7, 22.5, 21.4, 20.8, 18.1, 17.0, 14.0.
3H), 0.91 (d, J = 7.1 Hz, 3H), 0.84 (s, 3H). 13C NMR
(150 MHz, CDCl3): δ 199.4, 178.0, 140.6, 139.0, 84.8, 52.2,
50.5, 46.3, 44.5, 38.7, 37.5, 36.8, 35.6, 34.8, 25.8, 21.2, 17.9,
17.7, 16.8, 16.3, 14.3.
2.3 | Preparation of β,γ-unsaturated
ketone 3
2.5 | Preparation of alcohols 6 to 9
A mixture of methyl abietate 2 (2 g; 6.3 mmol), diethyl
ether (450 mL), water (12 mL), potassium bicarbonate
(29.01 g; 0.3 mmol), and iodine (6.36 g; 28 mmol) was
stirred at room temperature in argon atmosphere for
24 hours. Then, an excess of iodine was destroyed by
washing the mixture three times with 10% aqueous
sodium thiosulfate. The organic layer was dried over
Na2SO4 and evaporated to dryness. The residue was
chromatographed on silica gel to yield 1.29 g (60%) of
ketone 3 with melting point and spectroscopic data con-
sistent with the literature.14
A mixture of enone 3 (400 mg, 2.32 mmol), sodium tert-
butoxide (6.0 mg, 0.06 mmol), and anhydrous toluene (20.0
mL) was stirred with access to air at room temperature for
24 hours. Then the mixture was poured into water and
extracted with toluene. An organic layer was dried over
sodium sulfate and evaporated to dryness. The residue was
chromatographed on silica gel (10% ethyl acetate in hex-
ane) to yield alcohols 6 (108 mg, 23%), 7 (43 mg, 9%),
8 (124 mg, 25%), and 9 (26 mg, 6.0%) with spectroscopic
data of 6 to 8 consistent with the literature.14
1
1
3: colorless crystals, mp 86-88ꢀC; H NMR (500 MHz,
6: colorless oil; H NMR (500 MHz, CDCl3): δ 6.74
CDCl3): δ 5.81 (s, 1H), 3.64 (s, 3H), 2.88 (br d, J = 10 Hz,
1H), 2.41 (t, J = 14.2 Hz, 1H), 2.22 (septet, J = 6.8 Hz,
1H), 2.15 (dd, J = 14.2, 3.0 Hz, 1H), 2.08-1.84 (m, 5H),
1.80-1.71 (m, 1H), 1.70-1.59 (m, 3H), 1.37-1.28 (m, 2H),
1.22 (s, 3H), 1.07 (s, 3H), 1.14-1.05 (m, 1H), 1.00 (d, J =
6.8 Hz, 6H). 13C NMR (125 MHz, CDCl3): δ 208.8, 177.8,
144.6, 115.2, 52.9, 52.1, 49.1, 48.8, 47.2, 40.9, 37.3, 36.8,
36.0, 34.8, 26.6, 22.5, 21.6, 21.1, 17.8, 16.0, 13.6.
(br s, 1H), 3.66 (s, 3H), 2.40-2.24 (m, 3H), 2.10-2.05 (m,
1H), 1.86 (br d, J = 13.0 Hz, 1H), 1.80-1.68 (m, 4H),
1.66-1.60 (m, 2H), 1.60-1.53 (m, 2H), 1.50-1.45 (m, 2H),
1.25 (s, 3H), 1.25-1.18 (m, 1H), 0.96 (d, J = 6.8 Hz, 3H),
0.88 (s, 3H), 0.86 (d, J = 6.9 Hz, 3H). 13C NMR (125 MHz,
CDCl3): δ 199.3, 178.1, 140.1, 138.4, 71.8, 52.1, 51.7, 46.3,
44.4, 38.6, 37.9, 37.8, 36.9, 35.5, 29.5, 18.3, 17.8, 17.3, 16.4,
16.1, 14.4.
7: colorless crystals, mp 129-130ꢀC. 1H NMR
(500 MHz, CDCl3): δ 6.75 (br s, 1H), 3.66 (s, 3H),
2.39-2.31 (m, 2H), 2.28-2.20 (m, 2H), 2.17-2.12 (m, 1H),
1.82-1.55 (m, 7H), 1.48-1.36 (m, 3H), 1.27-1.17 (m, 1H),
1.24 (s, 3H), 0.98 (d, J = 6.8 Hz, 3H), 0.94 (d, J = 6.8 Hz,
3H), 0.86 (s, 3H). 13C NMR (125 MHz, CDCl3): δ 199.5,
178.0, 141.3, 136.8, 72.5, 52.2, 50.7, 46.4, 45.1, 39.0, 37.4,
36.8, 36.2, 35.9, 32.8, 20.5, 17.8, 17.0, 16.7, 16.2, 14.1.
8: colorless crystals, mp 115-118ꢀC. 1H NMR
(500 MHz, CDCl3): δ 5.25 (s, 1H), 3.88 (s, 1H), 3.67 (s,
3H), 2.52 (t, J = 14.1 Hz, 1H), 2.26-2.16 (m, 3H), 2.14-2.04
(m, 3H), 1.94-1.92 (m, 2H), 1.77-1.70 (m, 2H), 1.67-1.56
(m, 4H), 1.22 (s, 3H), 1.11 (s, 3H), 1.01 (d, J = 6.9 Hz,
6H). 13C NMR (125 MHz, CDCl3): δ 212.9, 177.8, 151.3,
118.9, 74.9, 55.1, 52.2, 47.6, 47.1. 39.8, 38.38, 38.35, 36.6,
35.2, 24.1, 21.2, 20.9, 17.5, 17.3, 16.7, 15.1.
2.4 | Preparation of hydroperoxides
4 and 5
A solution of enone 3 (500 mg; 1.5 mmol) in THF
(15 mL) and triethylamine (1.5 mL; 10.76 mmol) was
stirred at room temperature for 48 hours. with access to
air. Then solvents were evaporated to dryness. The resi-
due was chromatographed on silica gel to yield
4 (378 mg, 68%) and 5 (65 mg, 11%) with spectroscopic
data of both consistent with the literature.14
4: colorless crystals, mp 123-125ꢀC; 1H NMR
(500 MHz, CDCl3): δ 7.31 (br s, 1H), 6.81-6.79 (m, 1H),
3.66 (s, 3H), 2.42-2.20 (m, 4H), 2.08-2.04 (m, 1H),
1.89-1.81 (m, 2H), 1.79-1.43 (m, 7H), 1.25 (s, 3H),
1.24-1.17 (m, 1H), 0.91 (d, J = 6.9 Hz, 3H), 0.88 (s, 3H),
0.85 (d, J = 6.9 Hz, 3H). 13C MNR (125 MHz, CDCl3): δ
198.9, 178.1, 141.3, 136.8, 83.3, 52.2, 51.5, 46.3, 44.4, 38.7,
38.0, 36.9, 35.5, 32.7, 25.8, 18.7, 17.8, 17.2, 16.4, 16.2, 14.4.
1
9: colorless crystals, mp 80-81ꢀC. H NMR (400 MHz,
CDCl3) δ 5.93 (dt, J = 2.1, 1.0 Hz, 1H), 3.66 (d, J = 1.9
Hz, 3H), 3.06 (dd, J = 14.4, 13.2 Hz, 1H), 2.27-1.96 (m,
5H), 1.86-1.70 (m, 6H), 1.69-1.53 (m, 6H), 1.48 (s, 1H),
1.23 (s, 3H), 1.18-1.16 (m, 3H), 1.02 (d, J = 1.7 Hz, 3H),
1.00 (d, J = 1.7 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ
208.2, 178.2, 150.41, 119.1, 74.2, 55.8, 52.3, 50.1, 47.8,
38.6, 38.0, 36.9, 35.0, 27.9, 21.7, 21.3, 17.6, 17.1, 16.2, 15.6.
HRMS (ESI) m/z: [M + Na]+ Calcd for C21H32O4Na
371.2198; Found 371.2201.
1
5: colorless oil; H NMR (600 MHz, CDCl3): δ 7.98
(br s, 1H), 6.84 (dd, J = 2.3, 1.6 Hz, 1H), 3.66 (s, 3H),
2.39-2.33 (m, 2H), 2.28-2.21 (m, 2H), 1.97 (septet, J = 7.0
Hz, 1H), 1.95-1.87 (m, 2H), 1.83 (qd, J = 13.3, 4.0 Hz,
1H), 1.78-1.64 (m, 4H), 1.64-1.53 (m, 1H), 1.44-1.36 (m,
1H), 1.23 (s, 3H), 1.25-1.17 (m, 1H), 0.96 (d, J = 6.9 Hz,