1320
Helvetica Chimica Acta – Vol. 89 (2006)
with 1,2-dichloroethane (3×20 ml) and the combined org. layer washed with ice-water (3×20 ml), dried
(Na2SO4), and evaporated. The crude hydroquinone 2 was added to a stirred a suspension of KOH (3.67
g, 65.5 mmol) and Bu4NBr (0.1 g) under N2, maintaining the temp. at or below 208. Benzyl bromide (11.1
A
g, 65.5 mmol) was then added dropwise within 20 min under vigorous stirring, and the mixture was stirred
for 3 h under reflux. After cooling to r.t., H2O (100 ml) was added, the resulting mixture extracted with
Et2O (3×40 ml), the combined org. layer washed with brine (2×100 ml), dried (MgSO4), and evaporated,
A
and the crude product purified by CC (SiO2, petroleum ether): pure 3 (12.36 g, 94%). Colorless oil. 1H-
NMR (500 MHz, CDCl3): 1.57 (br. s, Me); 1.66 (s, Me); 2.11 (s, Me); 3.38 (d, J=7.3, CH2); 3.94 (s, 2
MeO); 4.94 (s, 2 CH2O); 5.43 (t, J=7.3, CH=C); 7.26–7.41 (m, 2 Ph). EI-MS: 432 (M+), 249, 219, 91.
(2E)-4-[2,5-Bis(benzyloxy)-3,4-dimethoxy-6-methylphenyl]-2-methylbut-2-en-1-ol (5). To a stirred
suspension of SeO2 (5.5 g, 46 mmol) in EtOH (100 ml) was added 3 (10 g, 23 mmol ) at r.t. The reaction
mixture was stirred under reflux for 2 h and filtered. The solvent was evaporated, the residue extracted
with Et2O (3×40 ml), and the combined org. layer washed with brine (2×100 ml), dried (MgSO4), and
G
evaporated. A soln. of NaBH4 (0.7 g, 18.4 mmol) in MeOH (150 ml) was added to the residue, and the
mixture was stirred for 30 min at 08. Sat. aq. NH4Cl soln. was added dropwise, and the aq. layer was
extracted with Et2O. The combined org. layer was washed with sat. aq. NaCl soln. (3×40 ml) and H2O
G
(3×25 ml), dried (MgSO4), evaporated and the crude product purified by CC (SiO2; petroleum ether/
1
AcOEt 8 :1): pure 5 (6.70 g, 65%). Colorless oil. IR (film): 3410, 2932, 1640, 1455, 1104, 1030, 698. H-
NMR (500 MHz, CDCl3): 1.63 (s, OH); 1.71 (s, Me); 2.30 (s, Me); 3.32 (d, J=8, CH2); 3.95 (s, 2
MeO); 3.97 (s, CH2); 5.16 (d, J=15.5, 2 CH2); 5.83 (t, J=7, CH=); 7.15–7.23 (m, 2 Ph). EI-MS: 448
(M+), 431, 363, 265, 249, 91.
1,4-Bis(benzyloxy)-2-[(2E)-4-bromo-3-methylbut-2-enyl]-5,6-dimethoxy-3-methylbenzene (6). To a
soln. of 5 (1.12 g, 2.5 mmol) in CH2Cl2 (10 ml) at 08, successively CBr4 (1.08 g, 3.25 mmol) and poly-
mer-supported triphenylphosphine (1.25 g, 3.75 mmol) was added. The suspension was stirred at 08 for
4 h and then filtered. The solvent was evaporated and the excess of CBr4 removed in vacuo: pure 6
(1.22 g, 95.3%). Colorless oil. 1H-NMR (500 MHz, CDCl3): 1.72 (s, Me); 2.10 (s, Me); 3.35 (d, J=8,
CH2); 3.94 (s, CH2); 3.95 (s, 2 MeO); 5.02 (t, J=15, 2 CH2); 5.83 (t, J=7, CH); 7.33–7.43 (m, 2 Ph).
EI-MS: 512 (M+), 431, 340, 249, 91.
1,4-Bis(benzyloxy)-2-{(2E,6E,10E,14E,18E,22E,26E,30E,34E)-3,7,11,15,19,23,27,31,35,39-decame-
thyl-5-[(4-methylphenyl)sulfonyl]tetraconta-2,6,10,14,18,22,26,30,34,38-decaenyl}-5,6-dimethoxy-3-meth-
ylbenzene (7). To a stirred soln. of 6 (5.11 g, 10 mmol) and solanesyl p-tolyl sulfone (6.03 g, 8 mmol) in
THF/DMF 9 :1 (100 ml) was added tBuOK (1.58 g, 14 mmol ), at ꢀ408 under N2. Stirring was continued
at ꢀ408 for 1.5 h, and further at 208 for 1 h. The mixture was poured into sat. aq. NH4Cl soln. (150 ml)
and extracted with Et2O (3×40 ml), the combined org. layer washed with 1M aq. HCl soln. (3×25 ml) and
E
H2O (3×25 ml), dried (Na2SO4), and evaporated, and the crude product purified by CC (SiO2, petroleum
ether/AcOEt 8 :1): pure 7 (8.08 g, 85.3%). Colorless oil. 1H-NMR (500 MHz, CDCl3): 1.51(s, MeC); 1.68
(s, 8 MeC); 1.67, 1.73 (2s, 2 Me); 1.85–2.16 (m, 8 CH2CH2); 2.70 (d, J=6.5, CH2); 3.20 (s, CH2); 3.40–3.55
(m, CH); 3.91 (s, 2 MeO); 4.83 (d, J=10.1, CH2); 4.89 (s, CH2); 5.0 (s, C=CH); 5.10 (s, 2 CH2O, 9 C=
CH); 7.28 (d, J=8.2, Ph); 7.70 (d, J=8.2, Ph). MALDI-MS: 1207.8 ([M+Na]+, C79
N
N
Coenzyme Q10 (=2-[(2E,6E,10E,14E,18E,22E,26E,30E,34E)-3,7,11,15,19,23,27,31,35,39-Decame-
thyltetraconta-2,6,10,14,18,22,26,30,34,38-decaenyl]-5,6-dimethoxy-3-methylcyclohexa-2,5-diene-1,4-
dione; 1): A freshly prepared soln. of 1M naphthalenyllithium in THF (10 mmol, 10 ml) was added drop-
wise to a soln. of 7 (1.18 g, 1 mmol) in THF at ꢀ788. The mixture was stirred for 2 h at ꢀ788 before being
warmed up to 08, quenched with sat. aq. NH4Cl soln. (20 ml) and extracted with Et2O (3 ml). The com-
E
bined org. layer was washed with sat.aq. NaCl soln. (2×15 ml) and H2O (2×15 ml), dried (Na2SO4), and
evaporated and the crude product purified by CC (SiO2, hexane/THF 9 :1). The obtained orange solid
was recrystallized from EtOH at 08: pure 1 (0.67 mg, 77%). Orange crystals. M.p. 48.3–498 ([3d]: m.p.
1
48–498). Purity ꢁ98.5% (by HPLC). H- NMR (500 MHz, CDCl3): 1.57, 1.59 (2s, 9 MeC=C); 1.69 (s,
MeC=C); 1.72 (s, MeC=C); 2.03 (s, arom. Me); 1.98–2.11 (m, 9 (CH2)2CH=); 3.18 (d, J=6.9, CH2);
G
3.96 , 4.01 (2s, 2 MeO); 4.90 (t, J=7.3, CH); 5.02–5.14 (m, 9 C=CH). MALDI-MS: 885.6 ([M+Na]+,
C59H90O4
Na+).
A
N
ACHTREUNG