3996
A. Srikrishna, G. Satyanarayana / Tetrahedron: Asymmetry 16 (2005) 3992–3997
(
1.5 ml), methoxymethyl chloride (0.33 ml, 4.39 mmol)
Anal. for C H O, Calcd: C, 81.76; H, 10.98. Found:
15 24
and a catalytic amount of DMAP was added slowly
DIPEA (0.75 ml, 4.39 mmol). The reaction mixture was
stirred for 16 h at room temperature. It was then diluted
with water and extracted with CH Cl (3 · 5 ml). The
C, 81.63; H, 11.13.
Further elution of the column using ethyl acetate–hex-
ane (1:25) as eluent furnished the first diastereomer of
isotwistane 16a (16 mg, 16%) as a colourless solid, which
was recrystallised from a mixture of CH Cl and hexane.
2
2
organic phase was washed with brine and dried over
Na SO . Evaporation of the solvent and purification
2
4
2
2
2
D
4
of the residue over a silica gel column using ethyl
acetate–hexane (1:20) as eluent furnished an epimeric
Mp: 111–114 ꢁC. [aꢂ ¼ ꢀ17:2 (c 1.1, CHCl ). IR (neat):
ꢀ
max 3 4
3
1
1
m
/cm 3574. H NMR (300 MHz, CDCl +CCl ): d
2
D
3
mixture of the ether 15 (120 mg, 68%) as oil. ½aꢂ
¼
4.74 (1H, d, J 6.6 Hz) and 4.47 (1H, d, J 6.6 Hz)
ꢀ
1
ꢀ
74:9 (c 5.5, CHCl ). IR (neat): m /cm 1714, 921.
3 max
H NMR (300 MHz, CDCl +CCl ): d 5.71 (dd, J 17.7
[OCH O], 3.31 (3H, s, OCH ), 2.32 (1H, q, J 7.8 Hz),
2
3
1
1.95–1.80 (1H, m), 1.84 (1H, dd, J 10.8 and 2.4 Hz),
3
4
and 11.1 Hz) and 5.66 (dd, J 17.4 and 10.8 Hz) [1H,
1.72–1.55 (2H, m), 1.60–1.35 (2H, m), 1.34 (3H, s,
CH@CH ], 5.25 (dd, J 10.8 and 1.2 Hz) and 5.16 (dd,
tert-CH ), 1.20 (1H, br s, OH), 1.20-1.00 (2H, m), 1.08
2
3
J 11.1 and 1.2 Hz) [1H, CH@CH ], 5.14 (dd, J 17.4
(3H, s, tert-CH ), 0.97 (3H, d, J 7.8 Hz, sec-CH ), 0.97
2
3
3
1
3
and 1.2 Hz) and 5.06 (dd, J 17.7 and 1.2 Hz) [1H,
(3H, s) and 0.90 (3H, s) [2 · tert-CH ]. C NMR
(75 MHz, CDCl +CCl ): d 91.5 (CH , OCH O), 84.1
3
CH@CH ], 4.62 and 4.60 (1H, d, J 6.9 Hz) and 4.45
2
3
4
2
2
and 4.30 (1H, d, J 6.9 Hz) [OCH O], 3.33 and 3.31
(C, C–OCH ), 82.2 (C, C–OH), 55.3 (CH , OCH ),
2
2 3 3
(
1
3H, s, OCH ), 2.23–1.95 (1H, m), 1.95–1.85 (1H, m),
.77–1.34 (6H, m), 1.23 and 1.14 (3H, s), 1.13 and 1.10
49.3 (CH), 46.7 (CH), 44.8 (C), 41.6 (C), 38.0
(CH), 27.9 (2C, CH ), 26.9 (CH ), 25.4 (CH ), 25.3
3
2
3
2
(
3H, s), 1.09 and 1.08 (3H, s), 1.07 and 1.05 (3H, s)
(CH ), 23.7 (CH ), 22.8 (CH ), 11.7 (CH ). Mass:
3 3 3 3
+
1
3
[
2
4 · tert-CH ]. C NMR (75 MHz, CDCl +CCl ): d
m/z 222 (M ꢀOCH OMe, 11%), 221 (100), 220 (17),
3
3
4
2
21.4 and 221.1 (C, C@O), 142.9 and 140.2 (CH,
149 (10), 137 (24), 124 (30), 123 (20), 121 (22), 109
CH@CH ), 117.8 and 115.1 (CH , CH@CH ), 91.7
and 91.3 (CH , OCH O), 82.7 and 82.3 (C, C–O), 56.0
and 55.5 (CH , OCH ), 51.6 and 50.8 (CH), 46.8 and
(14), 95 (21). HRMS: m/z Calcd for C H O Na
2
2
2
17 30
3
(M+Na): 305.2093. Found: 305.2086. Anal. for
C H O , Calcd: C, 72.30; H, 10.71. Found: C, 72.54;
2
2
3
3
17 30
3
4
6.7 (C), 45.7 (C), 37.9 and 37.8 (CH), 35.2 and 35.1
H, 10.70.
(
CH ), 28.2 and 27.6 (CH ), 26.1 (CH ), 26.0 (CH ),
2
2
3
3
2
2
1
3.4 and 23.3 (CH ), 22.0 and 21.9 (CH ), 21.1 and
Further elution of the column using ethyl acetate–hex-
ane (1:20) as eluent furnished the second diastereomer
of isotwistane 16b (26 mg, 26%) as a colourless solid,
which was recrystallised from a mixture of CH Cl
2
3
2
+
1.0 (CH ). Mass: m/z 219 (M ꢀOCH OMe, 10%),
3
2
78 (10), 165 (12), 137 (100), 115 (82), 107 (10), 91
(
10). HRMS: m/z Calcd for C H O Na (M+Na):
17 28 3
2
24
3
03.1936. Found: 303.1937.
.6. (+)-(1R,3R,7S,8S)-2,2,6,8-Tetramethyltricyclo-
5.3.1.0 ]undec-5-en-3-ol 6
and hexane. Mp: 58–60 ꢁC. ½aꢂ ¼ ꢀ122:5 (c 2.8,
D
ꢀ
1
1
CHCl ). IR (neat): m /cm
3626, 3532. H NMR
3
max
4
[
(300 MHz, CDCl +CCl ): d 4.62 and 4.56 (2H, 2 · d,
3
4
3
,8
J 7.0 Hz, OCH O), 3.36 (3H, s, OCH ), 2.51 (1H, q, J
2 3
7
.8 Hz), 2.30 (1H, m of d, J 14.4 Hz), 1.95–1.80 (1H,
To a magnetically stirred solution of methoxymethyl
ether 15 (115 mg, 0.06 mmol) in dry THF (3 ml) was
added freshly cut sodium metal (151 mg, 6.57 mmol)
and the reaction mixture refluxed for 16 h. It was then
cooled to room temperature and the excess sodium
metal quenched carefully with ethanol, diluted with water
and extracted with ether (3 · 5 ml). The organic layer
was washed with brine and dried over Na SO . Evapo-
m), 1.74 (1H, dd, J 10.4 and 1.8 Hz), 1.60 (1H, ddd, J
14.4, 11.4 and 6.6 Hz), 1.40 (3H, s, tert-CH ), 1.35–
3
1.05 (5H, m), 1.06 (3H, s, tert-CH ), 1.01 (3H, d, J
3
7.8 Hz, sec-CH ), 0.97 (3H, s) and 0.86 (3H, s)
3
1
3
[2 · tert-CH ].
C NMR (75 MHz, CDCl +CCl ):
3
3 4
d 92.1 (CH , OCH O), 84.0 (C, COCH O), 82.1 (C,
2
2
2
C–OH), 55.7 (CH , OCH ), 51.2 (CH), 47.0 (CH), 43.7
3
3
(C), 42.2 (C), 37.6 (CH), 28.0 (CH ), 27.1 (CH ), 25.9
2
4
2
3
ration of the solvent and purification of the residue over
a silica gel column using ethyl acetate–hexane (1:40)
as eluent furnished the tricyclic alcohol 6 (17 mg, 19%)
as a colourless solid, which was recrystallised from a
mixture of CH Cl and hexane. Mp: 44–46 ꢁC.
(CH ), 25.7 (CH ), 25.4 (CH ), 24.9 (CH ), 23.8
2 2 3 3
+
(CH ), 14.4 (CH ). Mass: m/z 267 (M ꢀOCH -
3
3
2
OMe, 18%), 237 (17), 222 (10), 221 (100), 220 (29),
205 (11), 149 (13), 137 (32), 124 (45), 109 (26), 95 (32),
93 (25), 91 (9). HRMS: m/z Calcd for C H O Na
2
2
17 30
3
24
ꢀ1
½
aꢂ ¼ þ42:3 (c 1.7, CHCl ). IR (neat): m /cm
(M+Na): 305.2093. Found: 305.2102. Anal. for
C H O , Calcd: C, 72.30; H, 10.71. Found: C, 72.23;
D
3
max
1
3
509. H NMR (300 MHz, CDCl +CCl ): d 5.14 (1H,
3 4
17 30
3
br s, C@CH), 2.34 (1H, dd, J 17.4 and 4.4 Hz), 2.10–
H, 10.70.
1
.70 (4H, m), 1.67 (3H, s, olefinic–CH ), 1.75–1.50
3
(
(
(
3H, m), 1.40–1.25 (1H, m), 1.20–1.00 (2H, m), 1.09
4.7. (ꢀ)-(1R,3R,6S,7S,8S)-2,2,6,8-Tetramethyltricyclo-
1
3
3,8
[5.3.1.0 ]undecan-3-ol (patchouli alcohol) 1
6H, s) and 0.79 (3H, s) [3 · tert-CH ]. C NMR
3
75 MHz, CDCl +CCl ): d 139.0 (C), 118.3 (CH,
3
4
CH@C), 75.0 (C, C–OH), 45.0 (CH), 39.5 (C), 39.2
To a solution of the dehydropatchouli alcohol 6 (10 mg,
0.04 mmol) in dry methanol (2 ml) was added 5% Pd–C
(20 mg) and the reaction stirred at room temperature in
a hydrogen atmosphere, created by evacuative displace-
ment of air (balloon), for 12 h. The reaction mixture
was passed through a short silica gel column to remove
(
CH), 35.9 (CH ), 35.4 (C), 30.1 (CH ), 27.1 (CH ),
2 2 2
2
6.6 (CH ), 25.6 (CH ), 23.5 (CH ), 22.1 (CH ), 21.1
3 3 2 3
+
(
CH ). Mass: m/z 220 (M , 64%), 205 (36), 149 (18),
3
1
37 (72), 121 (100), 107 (30). HRMS: m/z Calcd
+
for C H (M ꢀOH): 203.1800. Found: 203.1801.
1
5
23