(1.530 g, 4.1 mmol) was added. The temperature was adjusted
to 80 °C, and the solution was stirred for 2.5 h, cooled to room
temperature, and acidified with HCl solution (6 M) to pH ∼ 1.
The mixture was then extracted with dichloromethane (4 × 50
mL), and the organic phase was dried over Na2SO4. Evaporation
of the solvent, using a rotary evaporator, left a light yellow solid
(1.386 g, 98%) of 2 in a purity of 94% (GC). Crystallization from
dichloromethane:diethyl ether (3:1) gave 2 as white needles
R-(-)-Im p er a n en e (4). 3 (1.5 mmol, 0.554 g, purity 96%) was
dissolved in 40 mL of dry THF, and LAH (0.367 g, 9.7 mmol)
was portionwise added. The mixture was stirred at room
temperature under an atmosphere of argon (flame-dried glass-
ware) for 3.5 h. The reaction was then quenched by adding the
reaction mixture to 100 mL of distilled water. The pH value was
adjusted to 6 with 10% HCl, and the mixture was extracted with
dichloromethane (3 × 50 mL). The organic phase was washed
with 50 mL of saturated NaCl solution and dried over Na2SO4,
and the solvent was removed under reduced pressure. The
residue was dried under vacuum, yielding 0.424 g (83%) of 4 as
a white powder. Purity 94%. The product was further purified
by MPLC (ethyl acetate:petroleum ether, 1:1) to yield 0.266 g
(54%) of 4 in a purity g 98% (GC), 90% ee (HPLC), [R]22D -144°
(c ) 0.01 g/mL, C2H5OH), -103° (c ) 0.003 g/mL, CHCl3).
(1.068 g, 80%) in a purity of 98% (GC). Mp 126-128 °C, [R]22
D
-113° (c ) 0.03 g/mL, C2H5OH), 90% ee (HPLC).
HRMS m/z calculated for C19H20O6 (M+) 344.1260 found
1
344.1264. H NMR (500 MHz, CDCl3) δ 2.86 (1H, dd, J ) 13.8,
6.9 Hz), 3.11 (1H, dd J ) 13.7, 7.8 Hz), 3.41 (1H, dddd, J ) 8.7,
7.9, 7.0, 0.9 Hz), 3.78 (3H, s), 3.88 (3H, s), 6.08 (1H, dd, J )
15.8, 8.8 Hz), 6.36 (1H, d, J ) 15.4 Hz), 6.69 (1H, dd, J ) 7.9,
2.0 Hz), 6.72 (1H, d, J ) 1.9 Hz), 6.79 (1H, d, J ) 7.9 Hz), 6.81-
6.88 (3 H, m, complex). 13C NMR (125 MHz, CDCl3) δ 38.7, 51.6,
55.9, 55.9, 108.6, 112.1, 114.5, 114.7, 120.2, 121.9, 124.5, 129.4,
130.5, 132.7, 144.4, 145.8, 146.6, 147.0, 176.9. EIMS m/z (relative
intensity) 344 (13), 298 (5), 207 (5), 161 (7), 150 (12), 137 (100),
122 (2), 71 (6).
HRMS m/z calculated for C19H22O5 (M+) 330.1467 found
1
330.1470. H NMR (500 MHz, CDCl3) δ 2.62 (1H, m), 2.68 (1H,
dd, J ) 13.4, 7.0 Hz) 2.74 (1H, dd, J ) 13.4, 7.2 Hz), 3.56 (1H,
dd, J ) 10.7, 7.2 Hz), 3.66 (1H, dd, J ) 10.6, 4.7 Hz), 3.81 (3H,
s), 3.88 (3H, s), 5.54 (1H, s), 5.68 (1H, s), 5.92 (1H, dd, J ) 16.0,
8.3 Hz), 6.34 (1H, dd, J ) 15.9, 0.8 Hz), 6.66 (1H, dd, J ) 8.2,
2.0 Hz), 6.68 (1H, complex), 6.81 (1H, d, J ) 8.2 Hz), 6.80-6.85
(3H, complex). 13C NMR (125 MHz, CDCl3) δ 37.7, 47.6, 55.9,
55.9, 65.3, 108.3, 111.8, 114.2, 114.5, 119.7, 121.9, 128.4, 129.8,
131.5, 132.1, 143.9, 145.3, 146.3, 146.6. EIMS m/z (relative
intensity) 330 (41), 312 (14), 210 (21), 193 (49), 175 (58), 151
(54), 143 (17), 137 (100).
Met h yl (3E)-4-(4-H yd r oxy-3-m et h oxyp h en yl)-2-(4-h y-
d r oxy-3-m eth oxyp h en ylm eth yl)bu t-3-en oa te (3). 2 (purity
98%, 0.554 g, 1.6 mmol) was dissolved in 55 mL of methanol,
and 0.1 mL of 4:1 methanol-concentrated H2SO4 (0.36 mmol)
was added. The solution was stirred for 17 h at 50 °C and then
poured into 70 mL of saturated NaCl solution. The mixture was
extracted with dichloromethane and the organic phase dried over
Na2SO4. Evaporation of the solvent gave 0.569 g (99%) of 3 in a
purity of 93% (GC). Crystallization from dichloromethane-ether
(1:1) gave 0.40 g (70%) of 3 as a yellow solid. Mp. 143-144 °C.
Ack n ow led gm en t. The authors thank Hormos Nu-
traceutical Ltd., Turku, Finland, for the financial sup-
port of this work, Mr M. Reunanen, Laboratory of Forest
Product Chemistry, A° bo Akademi University, Turku,
Finland, for the HRMS analyses, Mr. C. Eckerman,
Laboratory of Forest Product Chemistry, A° bo Akademi
University, Turku, Finland, for the supply of hydroxy-
matairesinol, and Annika Smeds, Department of Or-
ganic Chemistry, A° bo Akademi University, Turku,
Finland, for the Chiral HPLC-MS analyses.
[R]22 -129° (c ) 0.02 g/mL, C2H5OH), purity by GC 97%, ee
D
90% (HPLC).
HRMS m/z calculated for C20H22O6 (M+) 358.1416 found
1
358.1422. H NMR (500 MHz, CDCl3) δ 2.85 (1H, dd, J ) 13.7,
6.9 Hz), 3.08 (1H, dd J ) 13.7, 8.1 Hz), 3.40 (1H, dddd, J ) 8.9,
8.0, 6.9, 0.8 Hz), 3.65 (3H, s), 3.81(3H, s), 3.88 (3H, s), 6.06 (1H,
dd, J ) 15.8, 8.8 Hz), 6.32 (1H, d, J ) 15.9 Hz), 6.66-6.69 (2H,
m, complex) 6.81 (1H, d, J ) 8.5 Hz), 6.80-6.86 (3H, m, complex).
13C NMR (125 MHz, CDCl3) δ 38.9, 51.7, 51.9, 55.9, 55.9, 108.2,
111.8, 114.3, 114.4, 120.2, 121.8, 124.6, 129.3, 130.6, 132.5, 144.2,
145.6, 146.3, 146.7, 174.2. EIMS m/z (relative intensity) 358 (17),
299 (3), 222 (16), 190 (7), 175 (29), 161 (25), 137 (100), 122 (3).
J O025985C
7546 J . Org. Chem., Vol. 67, No. 21, 2002